Construction Research Congress 2010: Innovation for Reshaping Construction Practice

On tunneling projects, a tunnel boring machine (TBM) operator heavily counts on experiences to steer TBM and control tunnel alignment, which can be error prone due to lack of visualization of the underground working environment. Any alignment errors may considerably increase the chances of a TBM accidentally ramming into unexpected man-made barriers or hidden boulders, potentially damaging the drill bits of the TBM or even causing the TBM to be trapped underground. To improve the situation, an innovative TBM guidance system was developed by integrating automated site data collection technologies and 4D construction planning models. The as-designed tunnel, the existing facilities nearby are integrated in a 4D production model, and the data collected by total station and sensors are transformed to kinematic parameters through on-line computing which generates a 3D graphic interface for visualizing the underground situation and the orientations of the rear and cutter head of the working TBM.

A contractor usually employs observers or employees to collect information from construction sites to verify the progress. The accuracy level of these field data significantly decreases because of the human errors and limitations in data availability. This paper describes a novel conceptual model called "Automated Multiple Objects Tracking System (AMOTS)" using latest technologies such as audio and video surveillance. The system tracks objects (workers, tools, etc.) based on the characteristics of the objects (unique shape of the objects and the unique sound patterns of the tools). A well-known correlation method and image subtraction method are applied to detect and differentiate the objects of the site. AMOTS also measures the real time work performance of the workers.

Industrial steel construction deals with the design, fabrication, and site erection of steel elements and encompasses many activities, interactions, and potential resources. An effective project control system for such an environment, as well as issues concerning traditional control systems, are important. This has motivated the authors to propose an integrated and real-time monitoring and control system for steel projects. This paper discusses the application of the concept of resource performance indicators in major components of the proposed system that deal with measuring project performance and the simulation of different scenarios. An object model is utilized and a control object is defined for steel projects to ease the control process. The focus of this research is on labour performance indicators in the fabrication phase of industrial steel projects. To improve the accuracy of the outputs of the system, the Markov Chain method has been used to forecast the values of the resource performance indicators that are fed into the simulation model.

In recent years, researchers have made considerable efforts to develop proximity sensing technologies that provide workers and equipment operators with an audible warning when predefined proximity thresholds have been breached. Examples of such technologies include RFID and Ultra-wideband sensors. Despite the practical applications of these technologies to safety management, implementation of such devices on active construction projects is very rare. In this paper, the authors identify the potential barriers and enablers associated with integrating sensing technologies within existing safety management strategies by interviewing safety managers throughout the United States. Using the findings from these interviews, the authors offer a framework for effective integration. It is expected that this framework can be used by construction practitioners to better understand how sensing technologies can complement existing efforts and by researchers who aim to better understand the potential role of such technologies in safety management.

Successful, large scale field trials were conducted on two sites in Texas and Toronto using an integrated system of RFID tags, GPS technology, map software, and hand held computing to automatically track materials in the projects' respective lay down yards. This paper addressed the unresolved research question, that how will this technology impact projects if it is implemented upstream in the supply chain in an integrated and automated materials management system? This question is addressed by modeling the impact of automated materials tracking technology on increasing visibility within the construction supply chain. It is concluded that automated materials tracking has the potential to improve construction productivity, cost, and schedule performance.

Accurate and efficient tracking, analysis and visualization of the as-built status of projects are critical components of a successful project monitoring. Such information directly supports control decision-making and if automated, can significantly impact management of a project. In this paper, we describe an innovative automated approach for recognition of physical progress from unordered daily construction photologs and Building Information Models (BIMs) . First, we describe an automated approach to photo-realistically reconstruct the as-built in 4D and label scene for occupancy. The IFC-based BIM is subsequently fused into the as-built scene by a registration-step and is traversed and labeled for visibility. Finally a machine learning scheme built upon a Bayesian probabilistic model is introduced that automatically detects physical progress in presence of occlusions and demonstrates that progress tracking at schedule activity-level could be fully automated. We present results on automated tracking, analysis and visualization of two ongoing building projects.

Measuring and controlling productivity of critical activities will have a significant impact on the cost and time performance of a project. The current practice of acquiring productivity data is heavily dependant on manual collection and data entry; hence it is time consuming, costly and difficult. The objective of the present work is to investigate the automation of the activity sampling method for rapid and real time collection of productivity data. Activity recognition or classification is identified as the major challenge in activity sampling. The proposed method uses accelerometers for activity recognition and a framework was developed for construction activity classification using accelerometers. This paper discusses the preliminary investigation phase in lab environment with a single wired triaxial accelerometer attached to the body of the subject performing typical repetitive movements of a mason. The data patterns were distinct for different movements and hence the features extracted can be used in training for classifying various activity categories.

As the construction industry transitions towards green buildings, and the number of LEED certified facilities continues to increase, the question of how to evaluate as-built energy performance becomes more important. Most homeowners rely on a monthly bill to determine their electric consumption, which is not an effective way to understand the results of most energy-saving strategies. Real-time feedback and appliance-level information is necessary, but most solutions require extensive hardware sub-metering, with a high price due to the hardware and installation costs. We argue that, in order to achieve wide adoption, the solutions need to be simple, easy to install, inexpensive and be able to return the investment in a reasonable time. In this paper we first analyze and compare the different types of technologies that are currently available for allowing homeowners to monitor their energy expenditure. Then we discuss new approaches that balance the trade-off between information and cost, and present preliminary results from a prototype Non-Intrusive Load Monitoring (NILM) system we have installed in a building.

Tunnel Boring Machine ( TBM) has been extensively implemented in microtunneling and pipe jacking projects for constructing subsurface pipeline infrastructure. Commonly used laser systems for TBM guidance tend to suffer from instable performance and low accuracy, while the high complexity in the system design of some advanced solutions compromises the system reliability while driving up the technology's cost. This paper presents an in-house developed automated and cost-effective TBM guidance system. The TBM's positions are automatically surveyed by a robotic total station and real-time line and level deviations from as-designed tunnel alignment are derived instantaneously. Given the coordinates of three observation points on the TBM, the TBM's three rotation angles in the underground space are determined by a "point-to-angle" computing algorithm. The automated system was assembled in house and tested at a pipe jacking site in Hong Kong. Practical constraints and considerations associated with the system setup and field testing are discussed. The performances of the automated system are evaluated in terms of accuracy and timeliness by comparing the testing results against data sourced from current control practices.

The U.S. has more than 14 million miles of buried pipelines and utilities, many of which are in congested urban environments where several lines share the underground space. Errors in locating excavations for new installation or for repair/rehabilitation of existing utilities can result in significant costs, delays, loss of life, and damage to property (Sterling 2000). There is thus a clear need for new solutions to accurately locate buried infrastructure and improve excavation safety. This paper presents ongoing research being collaboratively conducted by the University of Michigan and DTE Energy (Michigan's largest electric and gas utility company) that is investigating the use of Real-Time Kinematic GPS, combined with Geospatial Databases of subsurface utilities to design a new visual excavator-utility collision avoidance technology. 3D models of buried utilities are created from available geospatial data, and then superimposed over an excavator's work space using geo-referenced Augmented Reality (AR) to provide the operator and the spotter(s) with visual information on the location and type of utilities that exist in the excavator's vicinity. This paper describes the overall methodology and the first results of the research.

Information has the best value when it is delivered to the correct place at the correct time in the required format. Many scholars have noted information and communication chaos in the construction industry. The "i - Booth" is a real time information management system, which functions as the hub of the real time information integration system, is a novel technology developed at the University of Calgary in 2006. The concept was tested in commercial building construction settings with positive improvements in terms of tool time, productivity, and worker satisfaction. The content of this paper includes the conceptual framework, Graphical User Interface (GUI) development, and system building & verification process of the "i - Booth". The challenges under worker, management, technological, automation, and external issues during the development of the interface of the "i-Booth" are also explained in the paper. The multi-point capability of the system is expected to enhance the integration of the design office, the construction office, and the site staff as well as improve tool time, construction productivity, worker satisfaction, and communication.

Emerging wireless remote sensing technologies offer significant potential to improve the management of construction resources in lay down yards by tracking the location of personnel, yard vehicles, and materials in real-time. This paper presents a theoretical concept for real-time lay down yard asset management. A field trial using Ultra Wideband (UWB) positioning technology is presented to track spatial and temporal location of resources (workforce, equipment, material) that are present in lay down yards. The benefits and limitations of the technological approach which were applied in this research will be explained in detail and recommendations for its use in field tracking applications in large and open construction environments will be given. A particular focus of the paper is on the comparison of the accuracy of real-time location data from a commercial UWB system with ground truth measurements from a robotic total station.

For a light rail system, smooth contact between the vehicle and the guide beam is critical for reducing the friction and the vibration of an operating vehicle. Therefore, the shape of guide beams needs to be controlled with mm-level accuracy during the construction. Currently, most methods for detecting shape defects of guide beams, such as experimental run of vehicles, are costly and tedious, and can only identify defects after the completion of the construction, causing reworks and delays. From dense point clouds collected by laser scanners, inspectors can manually extract geometric features and conduct virtual inspections of guide beams. However, the manual geometric feature extraction process impedes effective utilization of point clouds for the shape analysis of guide beams. This research developed a semi-automatic approach for simultaneously extracting the axis parameters (e.g., radius) and cross-section features (e.g., width) of a guide beam using a Hough-Transform based approach, and discusses factors (e.g., data density) influencing the performance of this approach.

Equipment related fatalities account for about 25% of all construction fatalities in the United States. One leading indicator for equipment related incidents are blind spots that are prevalent around most construction equipment, inhibiting the operator's visibility of personnel and vital materials on jobsites. Incidents such as injuries and fatalities do occur because operators or ground personnel fail to identify that other objects can be in too close proximity to the work envelope they are operating in. This paper presents a new and unparalleled research approach to help identify the blind spots of equipment in order to quantify and protect the required safety zone(s) for such equipment. An automated blind spot detection tool is presented that determines the equipment blind spots rapidly and in 3D through analyzing the point cloud data from a laser scan inside the equipment cab. Terminology of planar and spatial blind spot measurements are defined and explained. Results to numerous vehicle types that were studied in the construction environment are presented and compared to existing manual and semi-automated methods for similarities. Future work and the applicability of automating the blind spot detection with alert technology in the construction industry are presented.

Perhaps the greatest challenge facing the cost estimating community over the next decade is the loss of knowledge and experience of highly experienced estimators as a high percentage of them are retiring and a shortage of qualified cost estimators is evident in the construction industry. This study identified 23 core estimating competencies classified into skills, knowledge, and personal attributes and also identified the gaps between the current and desired level of the estimating competencies. In total, 228 completed questionnaires were collected through the Construction Industry Institute (CII) member companies, and the Association for the Advancement of Cost Engineering —International (AACE-I) and American Society of Professional Estimators (ASPE) workshops. A criticality matrix was developed to prioritize competencies based on the combined effects of the level of importance of each competency and its associated gap. The factor analysis technique has been applied to investigate the correlation effects of the 23 estimating competencies. An implementation tool which assesses the current level of competencies of an estimator or an estimating team and recommends appropriate training tools has also been developed. The findings of this study will help engineering and construction companies design and develop appropriate educational and training programs to enhance estimating functions.

The Project Health Indicator (PHI).was developed because traditional measures and tools used during project design and construction to track project progress often do not identify potential problems in a timely manner. The PHI tool is based on the identification and assessment of "leading indicators." Leading indicators are fundamental project characteristics and/or events that reflect or predict project health. Revealed in a timely manner, these indicators allow for proactive management to influence project outcomes. The PHI tool contains 43 weighted leading indicators based on survey methodologies and ranking analysis. The PHI tool quantifies non quantifiable measures, that is, "Gut Feelings," and provides an early warning of potential problems. The tool was validated using completed projects by checking statistical correlations between tool output scores and cost and schedule performance indices. Industry users of the PHI tool have successfully applied it in practice. The objective of this paper is to describe the research methodology for tool development and how it is being successfully applied by industry.

Quality Management Systems in the capital facilities delivery industry were examined to identify best practices. The research surveyed 118 owner, contractor and supplier firms, performed statistical analysis of the responses, and conducted targeted structured interviews with 17 firms. The survey revealed several statistically significant areas where organizations with self-reported highly successful quality management systems differed from those organizations with self-reported less successful systems. Structured interviews were conducted to examine the practices of successful companies in greater depth. Through a synthesis of the results of the survey, the structured interviews, and a literature review, the research found that organizations with highly effective quality management systems had demonstrable management commitment with adequate resources for effective quality management; capable and consistent quality procedures across the organization; integrated and aligned quality management and project execution processes; effective training; strong partnerships with suppliers and contractors across the project life cycle; metrics that met organizational and project needs; and quality metrics used during all stages of engineering, procurement, construction, and start-up and commissioning. The survey results for leadership and third-party certification are presented here.

Integrated design process (IDP) and Building Information Modeling (BIM) have been recognized as two approaches to address the problem of fragmentation in the construction industry. Adopting these processes and tools nonetheless requires drastic changes in design practices. There is a need for generating and formalizing new knowledge practices, and discarding obsolete ones. However, traditional approaches to create and transfer this new knowledge cannot cope with this need. This research builds on social learning theories, such as activity theory, to propose a situated learning environment in which BIM-related technologies are structured in an IDP framework. This learning environment is designed as a laboratory where traditional practices in planning, managing and designing construction projects can be challenged. BIM and simulation models, together with collaboration tools are used as boundary objects to break barriers between professional practices. Design teams, by adapting to this new environment, generate new practice knowledge. This knowledge is captured using ethnographic methods to enhance and consolidate the IDP framework. The proposed approach contributes to accelerating the co-generation of new knowledge practices within the proposed environment.

Market demands for improved infrastructure and a more sustainable built environment are increasing the importance and scope of construction engineering throughout the project development process. Despite this, many construction programs face pressures to increase coverage of construction management topics, lessening time for construction engineering. These two opposing trends form the background for this paper. The goal of the paper is to provide compelling reasons and useful guidance to restore the balance between engineering and management in construction education. The method of analysis is to identify the priority fundamental elements of construction engineering knowledge and to describe the learning approaches applicable to each. The main contributions are a structure and methods for learning about construction engineering that are applicable to all types of construction. The paper also includes recommendations for educators to increase coverage of construction engineering using new learning approaches, for industry to assist in offering relevant courses, and for researchers to further develop construction process models and other tools with potential benefits for construction engineering education.

The competence of a construction program in the core area of construction project management is in imparting to its students the necessary expertise in order to practice professionally in the construction industry. The study identifies the competencies for baccalaureate level construction education in Alberta, Canada. To achieve the study objectives, a questionnaire survey was carried out to collect information on industry's perspective on construction professional competences. Responses from 32 construction industry professionals were analyzed. The results suggest that the construction acumen, project management and leadership, business acumen, professionalism, and communications were considered as the most important (top five) and desirable competencies for baccalaureate level construction education. Other important competencies include building techniques, international project management, research, cost management, conflict resolution, ability to learn, contracts management, risk management, teamwork, and technological competency, procurement management. It is recommended that the breadth and depth of the core's syllabi ensures sufficient coverage of fundamental and extended topics on construction project management. Construction programs should help to equip our students better to participate in the local and global construction industries that await them. The findings from this study would also be valuable for all academicians and researchers involved in the area of academic development in general.

Scientific literature and practical experience point out fragmentation of the building design process as one of the reasons for ineffective design and construction processes. This paper proposes interdisciplinary team learning in the context of an integrated design studio as a successful approach for both: achieving sustainable design solutions and transforming disciplinary cultures into integrated practices. In a rather unique collaborative experience based on strategies from situated learning and activity theory, students with different design and construction backgrounds were placed in multidisciplinary (co-located) teams to work on a real architectural project with specific requirements for sustainability. This integrated design studio was timed in three intensive 2-day charrettes. A coherent digital environment for integrated design was proposed in order to meet the needs of the multidisciplinary teams. The results from this experience were very positive in respect to both individual and team learning.

Previous studies have confirmed that industry internships help young faculty sharpen their teaching portfolios. Few studies, however, have explored the potential of research enhancement and the benefit that industry sponsors gain from the internship experience. This paper discusses how industry internships impact: (1) junior faculty's scholarship, and (2) industry sponsors' work. The paper presents an analysis of the authors' internship experiences through case studies with supporting data obtained from interviews involving industry personnel. The analysis suggests that an industry internship can, besides improve teaching methods, enhance the richness, quality, and scope of scholarly research and support industry sponsors. The paper also discusses a successful internship strategy and how the internship experience can be tailored to different faculty research areas. In the end, recommendations to guide future faculty internship programs are presented.

Interdisciplinary collaboration is becoming standard practice in the Architecture/Engineering/and Construction (AEC) industry. However, educational models in AEC have been slow to adjust to this rapid shift in project organization and execution. In recent years, industry leaders have expressed an increasing need for interdisciplinary professionals in the AEC industry. AEC education has great challenges ahead in order to address these needs. This paper explores the needs and challenges for interdisciplinary education in AEC and introduces initial efforts at the Georgia Institute of Technology to meet this need. The results of a survey of students, alumni and other groups are presented as well as the analysis of data from an on-line petition. Analysis of the data collected shows that there are conflicting views of the benefits of such an initiative. However, the results also highlight opportunities for enhanced collaboration through digital tools and greater inclusion of engineering departments in the process.

J. E. Dunn Construction Group and Iowa State University have collaborated in an innovative distance education program. By utilizing a micro-PC, digital camera and hands-free headset and microphone; jobsite personnel at the J. E. Dunn headquarters building construction site transmitted, via wireless technology, video imagery and voice information of real-time construction events to students in Iowa State University's Construction Engineering Program. Remote students seated in a high technology classroom were able to observe and discuss actual jobsite activity as it occurred 225 miles away. A series of "virtual" field trips were conducted covering several phases of the project, including site work, foundations, building structure and interior finishes. One of the virtual tours was led by J.D. Dunn's LEED specialist. In this tour, the guide specifically identified those building components earning LEED points for the project. Students, by and large, were pleased with the virtual site tours as the remote tours were less disruptive to their schedules and accomplished the same educational objective. Although this approach incurred certain technical difficulties, the information technology system performed satisfactorily and demonstrated promise for increased application of virtual construction site tours for many project stakeholders such as owners, architects, engineers, and lender representatives.

Various attempts have been made to apply Radio Frequency IDentification (RFID) technologies to current construction operations and processes; however, RFID applications have still required considerable investments and efforts to be successfully applied in the real construction projects. This paper examines the RFID technology applied to construction projects. A simulation model is developed to quantitatively evaluate the possible productivity benefits of RFID in construction. The model is based on the case study of a real construction project where the critical points of economically feasible solution for RFID application can be searched variable depending on the costs of RFID tags and RFID readers The simulation model also compares performances to apply RFID applications before and after. The results of simulation showed that RFID technology is effective for enhancing the project performances improvement at the operation and process level by reducing cycle time, decreasing queuing time, and improving other benefits including reliability of construction operations compared to invested costs. The results, however, also indicated that RFID application needs for further analysis in view of assessing qualitative aspects as well as implementation obstacles, based on more broaden case studies.

Simulation is a relatively new area of engineering research, whose implementation in day-to-day construction industry activities continues to lag behind research efforts. It is widely viewed that the lack of a visualization component in construction operations simulation contributes to this low level of adoption within the industry. This paper discusses the development of a framework for simulation visualization and the implementation of this framework in modeling a real pipe spools assembly yard and pipe modules site installations. The framework can be used to better represent spatial data in simulation. The framework is developed through a distributed simulation based approach using High Level Architecture (HLA) standards. The paper demonstrates how this research can benefit construction through a real case study.

Determining feasible mobile crane configurations and positions on a complex industrial construction projects that are free of spatial conflicts and the subsequent scheduling of the lifts is important to the productivity and safety of a project. This paper focuses on the integration of a crane dimensional and capacity database with a project's lifted object information to select and position the cranes and then utilize expert knowledge to simulate the heavy lift plan. The system uses dimensional and coordinate data instead of CAD software for computation of crane position areas amongst known obstructions and boundary limits. The crane position area is specific to a crane model and identifies where the center of rotation of the crane can be placed without having any part of the crane body contact the known obstructions and boundary limits. This analysis is performed for multiple cranes and lifted object scenarios to develop a list of possible options. Schedule date constraints and logic are used to simulate and optimize the schedule and crane selection. This provides the practitioner with an effective planning tool to select, position and schedule cranes.

This paper introduces a mathematical model and an optimizer to optimize dynamic variables of construction operations in multi-project environment. Vulnerable nature of construction schedules, resource limitations, multiple objectives, project uncertainties, business priorities and other inevitable constraints make the operations very challenging. The ultimate outcome of the model is to improve construction business efficiency and productivity in terms of profitability and resource management. The model consists of two main components; theoretical model and an optimizer. The first part is the formulation of the theoretical model considering all the multi-objective variables using mathematical descriptions, assumptions and equations. The second part is the solution using special purpose discrete-event simulation and genetic algorithms (GA) . An example with real life project data is presented to demonstrate the application of the proposed model. The results offer the best solution for conflicting objectives of minimizing multi-project schedules, maximizing resource utilization and maximizing the profit while satisfying all the imposed constraints.

The primary goal of the research is to investigate the discontinuities between current energy modeling tools and the implementation of sustainable features within the models they produce for better envelope design and construction material selection. From previous research efforts, it was discovered that energy modeling has made advances within their integration to early and mid level design phases, particularly through the use of Building Information Model (BIM) and the Green Build eXtensible Markup Language ( gbXML) file type. However, it was also discovered that BIM-integrated energy modeling tools are often lacking in their ability to incorporate renewable energy sources such as photovoltaic panels, wind turbine, and geothermal wells. This paper introduces strategies to include such sustainable fixtures to predict energy generation with a case study of Zero Net Energy Test Home(ZNETH) . In addition, this paper introduces parametric analyses for better envelope design and construction material selection by analyzing simulated energy consumptions with various parametric inputs, e.g., material types, location, and size.

Structural steel fabrication is influenced by both operation and context level effective factors. Usually the mechanisms through which operation level effective factors (e.g. capacity of equipment and operation sequences) affect the fabrication shop are properly documented within a variety of methods such as equipment manuals, job instructions, standards, quality control charts and ISO documents. However, while context level effective factors (e.g. operators' fatigue level and organizational policies) originate from human behavior, usually their enforcing paths are not well understood like operation based effective factors. This issue usually limits decision makers at steel fabrication shops to accept more inaccuracy by ignoring the effects of context level factors during their analyses. In an effort to address this issue, this research attempts to explore the effects of fatigue (as a context level effective factor) and its affecting dynamics within a steel fabrication shop. A hybrid model of system Dynamics and Discrete Event Simulation modeling approaches has been employed as the main tool for the research.

The Korean government has announced new policies to regulate mortgage lending, which aim to decrease both the Loan to Value ratio (LTV) and the Debt to Income ratio (DTI); this is due to the recent upturn in house prices and the increase in the number of mortgage loans that have been the result of deregulation policies such as increasing both the LTV and DTI, adopted in the second half of 2008. The government expects mortgage lending policies related in both the LTV and DTI to control housing demand and to stabilize house prices in the influence of market status. However, it is difficult to analyze how effective is these kind of policies on price and demand through an empirical approach. Also, because mortgage loan is a key element of real estate financial market, impact on secondary market in charge of mortgage securitization should be conducted. Consequently, a comprehensive and systematical method is necessary to analyze the effects of new government policies. This paper, therefore, utilizes an integrated perspective and applies a system dynamics methodology to develop Korean real estate market dynamics models. Using these system dynamics analysis, this research understands changes in housing market and mortgage lending agencies, as well as secondary financial market. In addition, the authors use system dynamics simulations to examine the interplay between mortgage loan variations, housing prices, and demand. This research found the missing links of empirical policy analysis and connected these links in order to expose the hidden side effects of these policies, as well as proposed comprehensive solutions and systematic approaches of dynamic systems.

The research presented in this paper focuses on understanding areas in which BIM is being utilized in general contracting companies and what these companies have as lessons learned from utilizing BIM. The authors conducted extended interviews with professionals (such as BIM managers, project managers, planners) from two different general contracting companies over various projects. The discussions were held such that each participant provided his/her experience over a project, where BIM was used for at least one phase of a construction project. The results of the discussions and interviews provided a wide range of case studies (in overall eight cases) on BIM utilization and lessons learned by project members related to BIM usage on these case projects. This paper provides an overview of each case project, introduces the phases of projects where BIM was helpful, and provides findings on lessons learned by project members with BIM usage. Practically, the lessons learned from these contracting companies can be helpful for construction professionals to improve their practices of BIM usage.

The management of equipment allocation for earthmoving operations is a complex dynamic series of discrete events. This paper presents a common and flexible Petri net model for the optimization of equipment allocation for a given construction period, cost and labor. A case study was conducted on a real construction project involving earthmoving operations. The data required by the research was collected on-site. A Petri net model was used to represent the dynamic constraint relationships among various types of equipment and their assigned tasks. The model describes the process workflow and equipment utilization for an earthmoving operation. The model was tested and sensitivity analysis carried out. Based on simulation results, and the given conditions, a minimum cost solution to the equipment allocation problem is obtained. This paper provides both practitioners and decision makers with a real study, a simulation model, and a useful approach to the equipment allocation problem in construction.

Data on construction resources (personnel, equipment, materials) is vast and the effort to collect and analyze it automatically is a priority in the construction industry. Once remote sensing and intelligent data processing technology are applied to supplement manual data recording, however, very few data visualization tools in construction exist that allow visualizing dynamic resource data in a field realistic virtual reality environment and are at the same time able to perform this task in or near real-time. Moreover, technology to assist in real-time data visualization and situational awareness can have a significant impact on stakeholders' successful and safe completion of construction projects. This research addresses the need for real-time data collection and visualization technology in construction applications. It reviews state-of-the-art technology in this field and presents a new framework that implements real-time remote sensing and data visualization technology in two significant construction applications: (1) Real-time pro-active construction safety assessment and training, and (2) Real-time construction productivity and performance monitoring. Preliminary results to each of these scenarios are presented and discussed.

Heavy lifting in industrial construction involves the installation of prefabricated modules and equipment weighing up to 1000 tons. Placing a prefabricated module requires a specific crane with a minimum capacity and specific configurations and riggings. Site construction process should follow a certain sequence. If the required cranes are not available or the predecessor modules or structures are not built yet, the module has to be stored in a storage area. Prior to lifting a module, several supporting tasks must take place including adjusting the location, configuration, and rigging of the crane and preparing the ground beneath the crane. Therefore, planning multiple heavy lifts is a complex process. However, it has a significant impact on the cost, schedule and safety of the project. This study employs a simulation-based approach to produce a heavy lifting planning system for mobile cranes. This system assists the project manager and lift engineer in decisions regarding the selection of mobile cranes and their locations and configurations for different lifts. It also produces a schedule that reduces the total cost and enhances the schedule of the project. This system is under implementation on an industrial plant in the province of Alberta, Canada.

Managing the behaviour and trajectory of an object lifted by a crane is critical to a successful lift. This paper presents advancements in the development of mathematical algorithms for lifted object trajectory paths and analyses. The proposed methodology is divided into smaller manageable phases to control the process and at the same time to create independent modules. Each step of the lifted object movement was geometrically tracked, starting at the lifted object pick-point, through an optimum path development and completing at the object final position (set-point). Parameters such as the minimum distance between the lifted object and passing obstructions and minimum allowable clearance between the lifted object and the crane boom are some of the many predefined rules which were taken into account. The lifted object's spatial trajectory analysis and optimization is a part of the complex assignment relating to the crane selection process. A numerical example is presented to demonstrate the effectiveness of the proposed methodology and illustrate its essential value.

Discrete-event simulation (DES) has long been used as a management tool to analyze and study construction processes. Project scheduling is one of its useful applications in construction domain. By simulating the behavior of a production system over time, the DES is able to reproduce the process of how jobs and resources interact with each other. A schedule can then be viewed a record of this artificial history. However, simulation-based scheduling is, more often than not, limited to create the initial schedules. The problem of how to update project schedule based on the current progress is rarely addressed in construction simulation research. This paper presents a state-based simulation approach that can facilitate project schedule updating by (1) reading the starting time (i.e. the point of time to update the schedule); (2) resuming the work load of production system at this time and running from there; and (3) updating the new schedule (from simulation) based on the As-Built project progress. An illustration example is used to illustrate how the new modeling approach is used to perform schedule updating and its benefits are discussed as well.

Construction projects consist of multiple components such as on-site equipment resources, site layout, labor productivity, unexpected external events, and human decisions regarding resource allocation and activity rescheduling. Stochastic spatial and temporal interactions between those components result in dynamic complexity of construction projects. Decisions made in such dynamic task environments must consider both immediate impacts and long-term dynamic feedback. The objective of this research is to use the adaptive interactive simulation framework as an experimental test bed to study dynamics of decisions in construction scenarios. A simulation of a four story structural steel framed office building project was implemented within Interactive Construction Decision Making Aid (ICDMA) under five different decision strategies. Simulated construction performance data at each decision control point was collected and analyzed to compare the project dynamics resulting from five strategies, and those strategies were assessed as well. This research provides a perspective to study dynamics of decision making through interactive simulation while furthering the knowledge of effective decision making and the development of dynamic decision support systems in construction management.

One of the keys to successful safety management is establishing a strong safety culture within a company. Because workers' behavior is influenced by the workers themselves, by their supervisors, and even by the top managers, understanding the dynamics among them is beneficial for establishing and sustaining a culture of safety on a project. To model safety dynamics, we review the literature for the relationship between a worker's personal care for safety and a strong safety culture. We also investigate, from the perspective of resilience engineering, how an organization can perceive a change in the safety culture and restore safety to an acceptable state. As a result, a conceptual system dynamics model is established for qualitative analysis, and the analysis reveals that the model can be applied to establish a resilience system for safety management and used to predict organization's future risk. Thus, a practical application of theories on a safety culture is presented, and with the model, managers can monitor the safety culture as arising from an interaction among workers, managers, and the organization, and can improve safety based on an organizational perspective.

Increasing performance pressure has forced modern construction enterprises to seek growth while dealing with inherent complexity of the construction business. Business complexity (fragmented business mode, organizational complexity, etc.) has been considered a major source of performance issues in the construction industry. Unfortunately, there has been no efficient way to estimate its effects on organizational or project performance. This paper proposes a simulation-based organizational analysis platform called "Virtual Organizational Imitation for Construction Enterprises" (VOICE) to assess and manage business complexity of construction enterprises. A series of Agent-Based Models (ABM) were built using Repast Simphony to explore the relationship between social behaviors, organizational factors, and emergent organizational and project performance. The platform allows decision makers to simulate individual social behaviors, organizational structures, and environmental aspects of construction enterprises. Initial findings show that these factors affect the final performance of construction enterprises to an extent. As a socio-technical system, business complexity should be understood, assessed, and managed well. Results indicate that VOICE is a reliable platform to capture patterns of business complexity.

Disasters such as earthquakes and floods are sudden events that are difficult to predict, but have catastrophic consequences. A critical issue in disaster management is timely evacuation. University campuses face a unique challenge in developing effective emergency evacuation plans due to the complex site and high-dense buildings and population. This paper presents a method to optimize the placement of road barriers in emergency evacuation and assess the effectiveness via simulation. The main campus of the Western Michigan University (WMU) was chosen to implement and test the developed method. The placement of road barriers was optimized and the results were validated, using the Transportation Analysis and Simulation System (TRANSIMS). This system was also used to test the effectiveness of evacuation time to phased evacuation notification. It concluded that placing road barriers at appropriate locations could reduce the evacuation time by 20% or more.

There has been a significant increase in natural disasters that have negatively affected the U.S. economy in recent decades. The Government Accountability Office reported that the U.S. is not well prepared to manage large-scale natural disasters either through emergency response or financial relief. It is essential to develop integrated post-disaster investment strategies that avoid many of the pitfalls that have been observed following recent catastrophic events. This paper proposes a conceptual framework to build theoretical foundation and demonstrate technologies for creating a decision support system for optimizing stakeholders' resource allocation in natural hazards. The proposed framework will: (1) minimize the total costs associated with implementing such investment strategies and (2) maximize the uniformity of welfare distribution among all associated parties. This would provide broad members of the emergency management community as well as policy makers with easy-to-use preparedness and decision support tool, which would help in creating better societal financial resilience towards natural hazards.

In the summer of 2008, two hurricanes made landfall along the Texas coast causing billions of dollars in damage. Texas received presidential disaster declarations, which resulted in the state receiving over $350 million in hazard mitigation funds. Over 500 requests for mitigation projects were submitted to the government from communities impacted by these disasters, but not all requested projects could be funded. As a result, those communities that submitted requests for well-defined mitigation projects were the primary benefactors of the federal mitigation funds. To better understand the factors that characterize a "well-defined" mitigation project, a study was initiated to develop an index for rating the completeness and quality of mitigation project definition. The study incorporated concepts from research on the quality of community planning and from project definition rating methods. A rating tool was developed to evaluate projects that have been successfully funded and to contrast them with projects that have been rejected. The rating tool consists of detailed descriptions of the project scope elements along with a method for scoring the completeness and quality of the project's definition. This paper presents the research results and the outcome from comparing six mitigation project definition packages.

In 2006 the U.S. Congress appropriated $400 million to the Department of Homeland Security to support post-disaster alternative housing pilot programs as a possible substitution to the highly criticized temporary housing programs. One of the main objectives of these programs is to provide quick and permanent housing solutions to displaced families. Decisions on alternative housing should be carefully analyzed because of their significant impacts on (1) socioeconomic welfare of displaced families; and (2) available budgets for post-disaster housing recovery. This paper presents the development of an optimization model capable of identifying the optimal alternative housing plans that maximizes the net social benefits of these programs. This is achieved by striking a balance between the added social benefits to displaced families provided by alternative housing and the corresponding associated costs. An application example is analyzed to demonstrate the use of the proposed model and its capabilities in maximizing net social benefits.

Critical infrastructure play an important role in functioning of industries and communities and also responding against natural disasters to reduce their impacts (i.e., routes and bridges for evacuation and public buildings for sheltering). Due to global warming, there is an increase in the frequency of extreme weather events which pose a high risk of functional and structural failure of critical infrastructure. Recent natural disasters (i.e., Hurricane Katrina, 2008 Midwest Flood, etc.) have exposed the vulnerability of critical infrastructure in the U.S. Therefore, it is important for the emergency-related agencies to identify and fortify the vulnerable critical infrastructure ahead of time to significantly reduce the potential damage due to floods. In this paper a decision support system (DSS) using Bayesian Network theory and System Dynamics Simulation method is presented for vulnerability assessment of critical infrastructure. This DSS has been developed to support emergency agencies and industries to prepare customized mitigation strategies and plans for preparedness, response, and recovery using the criticality and vulnerability analyses.

In construction sites, tracking personnel, equipment, and materials is necessary in many applications such as asset management and progress monitoring. Vision tracking as a tracking technique has two unique capabilities which make it ideal for tracking on large scale, congested construction sites; tracking from a distance and tracking multiple elements from a single camera. 2D tracking results can be obtained through each camera and the 3D positions can be calculated by calibrating multiple cameras. 2D vision tracking methods vary and each method has unique capabilities, but little is known about the appropriateness of each method for tracking construction resources. This paper presents an evaluation of these methods that aims to identify the one most suitable for 3D tracking in construction sites. To satisfy this goal, 2D tracking methods are categorized, metrics are identified and performance of two categories of methods is evaluated based on these metrics. This evaluation has been used to find some preliminary results that can ultimately help with selection of the most suitable category of 2D vision tracking methods for construction applications.

This paper presents a framework of decision support systems for facilities maintenance management (FMM) with the objective of integrating facilities maintenance management, real-time project management, condition monitoring systems and building information models. Multi-faceted views of maintainable assets are designed to meet the requirements of any potential functional extensions or systems integration. Basic processes for asset management, Corrective Maintenance (CM), Preventive Maintenance (PM), and Condition-based Maintenance (CBM) are implemented in a Web-based FMM prototype system. The generic aspects of the system lay in the fact that: 1) all sources of maintenance work, ranging from manually entered CM orders and system generated PM orders to individual maintenance projects, are normalized and manipulated as projects and tasks; 2) the allocation of various kinds of resources, including equipment, materials, trades, contractors, and tools, is optimized using the proposed algorithms.

Efficient request and deployment of resources such as construction equipment is vital to urban search and rescue operations during emergency response. Based on the lessons learned in recent disasters, collecting, prioritizing and distributing of resources are urgent to life-saving operations. Construction equipment is required for shoring of structures, selective debris removal, and lifting of heavy building components. Infrastructure restoration, such as the transportation network, also needs construction equipment to support its operations to bring back services to facilitate disaster response efforts. A Geographic Information System (GIS) framework is presented to expedite equipment management. Within the framework, automation of data collection, transfer and processing for fast decision-making via computer networks, geospatial services and mobile devices is proposed. With the framework deployed, lifesaving operations are expected to have better performance provided with the appropriate equipment.

This paper presents a simple, flexible and intuitive approach for activity sequencing and project scheduling. Several construction scheduling professionals were consulted during development of this approach. The most important attribute desired by the industry professionals was flexibility to rapidly revise activity definitions and relationships allowing fast schedule modifications and what-if analysis. Considering the needs and suggestions of construction industry professionals and using the latest visualization technology, a graphics application was developed using Microsoft DirectX Graphics Library. The application interfaces with Revit CAD software to extract a building project's geometry and material information which is then used to create a virtual prototype of the project. Users can walk inside the virtual building for visualization of the project and sequencing project activities by selecting tasks and predecessors. The application interfaces with MS Project and provides an intuitive and flexible method to digitally transfer activity information to the schedule. The visual approach presented in this paper attempts to increase scheduling efficiency by incorporating the findings of modern cognitive theories that suggest human brain interacts more effectively with 3D virtual worlds than a long list of project activities and textual content.

In the Architectural, Engineering, and Construction (A/E/C) industry, construction products constitute a large proportion of the total cost of construction. In recent years, the range of construction products has grown substantially that users are facing difficulties in selecting products that fit their projects' needs. Due to wide availability of the internet, web-based construction production information (CPI) providers have become very popular as a new source of CPI acquisition. This study identified a typical business operating structure of this new industry sector and also investigated various factors that are critical for successful operation of the business in the A/E/C industry in the United States, through extensive literature reviews, investigations of CPI websites, and three independent surveys of CPI users, web-based CPI providers and construction product manufacturers. The findings of this study will allow stakeholders to find areas to improve in order to continue to grow in this industry sector.

Various real-time field data acquisition systems have been developed aiming to automate control of construction projects. Some of those have demonstrated potential for automating project control to a certain extent and most of the systems support a specific function of project control. It is envisioned that successful integration of the systems would create new innovations and opportunities in managing the architecture/engineering/construction (AEC) projects. In an attempt to facilitate integration among real-time systems, this study explored the feasibility of using building information model as a base of integration. In this study, a large volume of literature was reviewed to understand the state of the art real-time project control systems and building information modeling (BIM). Upon the understanding, this study identified a list of conditions or requirements for successful integration. The findings presented in this paper are expected to provide guidelines that need to be taken into consideration when developing automated real-time systems and building information models.

Over the course of a typical construction project, project managers constantly monitor progress and resolve problems. However, it may be not easy to track and identify performance problems when a construction project generates a great volume and variety of ever-changing data during the construction phase. Traditionally, in order to identify performance problems, project managers walk job sites and meet or call several individuals. Since the advent of web-based tools, project managers have been able to obtain information by logging on to a project's web site. However, early efforts at using computers to manage construction projects came up short with technology that was awkward or costly. Today, thanks to advancements in information technology, web-based tools are capable of displaying information in easy-to-read graphics, assembled from data pulled from multiple sources in real time. This paper explores what data should be collected for web-based systems to provide project managers with threshold level information regarding actual project status so that they can focus on the "big picture." This exploration is based on literature review and interviews with fifteen project managers from construction firms in the Puget Sound area. The information presented in this paper may serve as the foundation for the development of visual information systems to support the work of construction project managers.

There have been several isolated attempts to automate aspects of the construction project delivery process. These have only been marginally successful and it is increasingly being recognized that significant improvements can only be made through an integrated approach that involves the synergistic integration of information technologies into the project delivery process. A cyber-physical systems approach is expected to reduce the tremendous losses that are directly attributable to the inefficiencies associated with the lack of effective integration. This paper describes a specific effort that seeks to facilitate real-time consistency checking between virtual models and the physical construction. It argues for the effective integration of computational resources (such as wireless sensors, virtual prototyping, real-time tracking and data fusion) with the design and construction process, and outlines how bi-directional consistency can be maintained between the virtual models (which are often ignored once the physical construction commences) and the physical facility. The opportunity offered by the adoption of a cyber-physical systems approach to make the construction process more intelligent and sustainable is discussed and the key benefits highlighted.

With the proliferation of building information modeling (BIM) in architectural design, there will be a rapidly increasing need to create accurate as-built BIM data for existing buildings. Having an accurate as-built model of the existing structure allows owners to visualize and analyze proposed retrofit solutions and ensures that the retrofit meets the owner's requirements and provides the best value. The increased awareness of building energy consumption, green gas emissions, and LEED^TM (Leadership in Energy and Environmental Design) also calls for new as-built documents based on BIM. This paper describes a approach for developing as-built BIM coupled with various data acquisition tools. Existing as-built technologies, such as 3D laser scanning, are reviewed and future uses for as-built BIM are suggested. The two case studies presented in this paper are part of an ongoing research project involving a local governmental agency building with significant renovation needs. The first describes a new method of acquiring building energy-related data: BIM paired with a sensor network. The second describes a method of creating as-built BIM using imported 2D plans. Finally, current challenges of as-built BIM technology are addressed to improve the future deployment of the proposed approach for as-built BIM.

This paper discusses the application of photogrammetric methods to monitor ground movements during trenchless construction projects. Ground movements are a concern as they can cause damage to buried utilities and surface structures. Photogrammetry is a remote sensing technique in which the geometric properties of objects and surfaces can be determined from photographic images. This technique allows for accurate three-dimensional measurements of specific points on the ground surface. Measurements are determined utilizing two or more photographs taken from different positions at specific time intervals. Photographs from specific time intervals are complied using photogrammetry software to determine the position of surface points in three-dimensional space. This paper provides an overview of the photogrammetric method, its application to trenchless projects, and results and analysis of data gathered from calibration and repeatability of measurement studies.

Bridge condition rating is used to make important decisions regarding needs assessment and budget allocation. This study analyzes the use of the fuzzy logic approach to overcome uncertainty problems associated with the bridge condition assessment process. The analysis reveals a number of practical difficulties associated with the application of the fuzzy mathematics to develop an overall bridge condition rating. An alternative probabilistic methodology to rate the bridge elements taking into account the uncertainty issue is developed. The Analytic Hierarchy Process is adopted to evaluate the structural importance of the various bridge elements. A technique is proposed to aggregate the condition rating and the structural importance of the bridge elements into an overall bridge condition rating. The developed methodology uses the detailed visual inspection results to perform bridge condition rating and blends perfectly with the popular Markov chain approach to model deterioration.

This paper presents a comprehensive data analysis of recent highway construction zone crashes in the state of Illinois to provide a better understanding of the characteristics of these crashes in order to identify effective safety measures to improve construction zone layouts. The two main research objectives of this data analysis are to (1) analyze the frequency and severity of work zone crashes; and (2) investigate probable causes and contributing factors of these work zone crashes. To accomplish these objectives, two main research tasks were performed that focused on: (a) gathering the most recent and comprehensive set of data and reports on highway construction zone crashes in Illinois; and (b) studying the correlation among all construction zone crash variables that are available in the gathered data to investigate probable causes and contributing factors of this type of highway crashes.

City managers and elected officials in many municipalities are frequently faced with the challenge to cater for public expectations on one hand and to comply with technical/engineering requirements on the other. This paper presents a four phased level of service driven reliability based methodology for allocation of budget to water mains. This methodology comprises of: (1) development of an Analytical Hierarchy model of LoS; (2) a sub-network criticality model to account for certain quantitative and qualitative characteristics of a given sub-network (3) a sub-network reliability assessment model and 4) a budget allocation model. Combination of the above contradicting requirements, i.e. level of service and network reliability, is expected to assist decision makers in quantifying the required condition improvement to meet service goals and to make more informed decisions on interventions and relayed priorities. To show the robustness of the developed models, a hypothetical case study is developed and analyzed.

Line leakage of oil and natural gas systems can result in significant financial and environmental consequences. Often, small leaks lead to ruptures in the pipeline that result in product escaping into the surrounding soil. Oil product can taint water supplies by migrating into aquifers, while natural gas leaks are susceptible to catastrophic explosions. A joint academic-industry research initiative funded by the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA) has lead to the development and refinement of a free-swimming device capable of detecting small leaks in oil product and natural gas pipelines. The SmartBall swims through a pipeline being assessed and produces results at significantly reduced cost to the end user compared to current leak detection methods. GIS based above ground loggers that are GPS synchronized capture low frequency acoustic signatures and digitally log the passage of the SmartBall through a pipeline. This paper presents the development, laboratory and field validation testing of the SmartBall for both oil and natural gas applications with discussion of demonstrated case studies.

The objective of this research is to analyze historical records of random non-mechanistic failures in civil infrastructure systems. In this paper, we particularly focus on blockage failures in sewer systems that result from combination of external factors, such as variations in usage loads, construction quality and soil characteristics. The study uses historical blockage failure records maintained by municipalities. However, such datasets often tend to be incomplete and/or not representative of failure patterns. We discuss the application of statistical tests — specifically the Kolmogorov-Smirnov (KS) test and Anderson-Darling (AD) goodness-of-fit test — to estimate (i) if the datasets are complete and representative enough, and (ii) estimate parameters of distributions that appropriately characterize failure event arrival pattern. A dataset consisting of sewer blockage failures for ten years from a small municipality in the State of Michigan was used. The methods discussed in this paper can be used to implement reliability models of other related infrastructure systems as well.

As an on-going project, the main objective of this research is to develop a framework for the functional and widely accessible Geographic Information System tools to track information collected throughout the highway construction and maintenance projects in the state of Nebraska. Microsoft's Bing Maps and Google's Google Earth are both being investigated for possible integration with the Nebraska Pavement Management System. A test system has been built utilizing an increasingly large data pool previously created from the past hot mix asphalt (HMA) projects. Different data types including: physically marked locations, digitally marked locations, density reads, moisture readings, weather information, and temperate segregation were linked together using Google Earth that can be accessible from the field or the office. The developed framework is identified as a feasible solution to supplement the existing Nebraska Department of Roads (NDOR) pavement management system(PMS) with an upgradeable, efficient, and user friendly web-based interface.

This paper examines how energy and infrastructure impact each other and what that means for carbon limits and peak oil. Throughout history mankind has always had ample sources of energy to rely on. This reliance on energy, particularly through the industrial revolution, allowed mankind to build a modern lifestyle. However, as infrastructure has evolved and become more complex the world has demanded greater supplies of energy. Initially this demand for energy was met with nearby supplies. However, as those supplies have decreased, more energy is needed from further and further away. This has meant that greater and more complex infrastructure has had to be built to supply the energy resources from greater distances. The easy energy resources have also been tapped resulting in a need to expend more energy to unlock the remaining sources of energy. Now, as the world ponders carbon limits and potentially faces peak oil the viability of our existing infrastructure and the energy that supports it is a cause for great concern. Are we taking into account our future energy sources as we build more and more infrastructure? In a world of constrained resources building infrastructure without regard to energy could significantly impact the price we pay for energy as well as the viability of the infrastructure. Infrastructure and energy is an important discussion as it will impact our standard of living and how we plan now for 2050.

The U.S. continues to face the challenge of correctly identifying underground utilities before beginning a construction project. Having accurately mapped utilities and knowing their location will increase efficiency in the construction process, reducing accidents and utility interruptions. A methodology to integrate Global Positioning System (GPS) and laser technology will be outlined. This process will assist field technicians in collecting underground utility field location data, accurately and consistently, in a minimal amount of time, with less effort, while maintaining maximum safety. It will also form a framework to develop a permanent data solution in which data collected can be stored in a database and retrieved in a three dimensional geo-referenced map for future use. This research focused on utilities which were installed using an open trench method. The integrated technology was tested under construction field conditions. The results of the research indicate that utility data can be collected quickly and cost effectively through this process. The positional accuracy of underground utilities was mapped in three dimensions (3D) within ± 0.45m accuracy.

Manually inspecting bridges is a time-consuming and costly task. There are over 600,000 bridges in the US, and not all of them can be inspected and maintained within the specified time frame as some state DOTs cannot afford the essential costs and manpower. This paper presents a novel method that can detect bridge concrete columns from visual data for the purpose of eventually creating an automated bridge condition assessment system. The method employs SIFT feature detection and matching to find overlapping areas among images. Affine transformation matrices are then calculated to combine images containing different segments of one column into a single image. Following that, the bridge columns are detected by identifying the boundaries in the stitched image and classifying the material within each boundary. Preliminary test results using real bridge images indicate that most columns in stitched images can be correctly detected and thus, the viability of the application of this research.

According to the Ministry of Land, Transport and Maritime Affairs, the price of social infrastructure asset, including nation-wide roads, railways, airports, harbors, water and sewage systems, and water resources management facilities, amounted to 515.2 trillion won as of 2004 (Ministry of Land, Transport and Maritime Affairs, 2007). When it comes to social infrastructure, the emphasis has been placed on the construction aspect for decades. But the need is being raised for more comprehensive management of the infrastructure. In most of developed countries, infrastructure asset management has been implemented for the effective and efficient operation and management of infrastructure. Infrastructure asset management is also being implemented in Korea. The purpose of this study was to review the current data collection methods to help implement better asset management and to address the need to utilize wireless sensor technologies and propose implementation strategies for the implementation.

This paper presents a semantic system for coordinating the management of infrastructure projects. The proposed system starts from three fundamental premises: the use of knowledge (through ontologies and semantic systems), covering all facets of infrastructure projects (products, processes and human actors), and consideration of project aspects other than direct costs.

With ageing water and sewer infrastructure in North America, assessing the condition of these assets has received increased attention in the past few years. Condition assessment is an integral component in any asset management program. Determining the condition of buried infrastructure tends to be more cumbersome, costly and error-prone compared to other surface infrastructure like roads and buildings. For sewers, CCTV is considered the industry standard for condition assessment technologies. For pressurized water pipelines, technologies tend to be more costly and uncertain (e.g. electromagnetic, sonar, acoustic leak detection, infrared etc...). Faced with constrained budgets and the need to obtain reliable condition information to drive their asset management processes, infrastructure owners must balance the value of information obtained through condition assessments with the cost of obtaining this information. This paper presents an analytical framework and decision support system to evaluate the value of information for condition assessments of water and sewer infrastructure. The framework considers: 1) risks associated with operating the asset, 2) potential direct and indirect costs of infrastructure failure, and 3) customer expectations for the system's level of service. The decision support system utilizes Partially Observable Markov Decision Process (POMDP) to compare between the reliability and cost of the condition assessment technology. The system is demonstrated on the water and sewer networks for the City of Hamilton, Canada.

A majority of construction projects often have a significant impact on the surrounding neighbourhoods and the environment at large. In city scale infrastructure projects, this impact can be detrimental to project success. The affected populations often have concerns and more importantly local knowledge relevant to the project. Capturing and integrating this feedback enhances project sustainability. This integration is a feature of smart city initiatives that have increased collaboration between regulatory bodies and project planners. However, the community has not been able to effectively engage in this process. Accordingly there is a need to facilitate two-way communication to promote community involvement beyond the capabilities of a smart city; this will be achieved through e-Society. An e-Society boosts citywide sustainability by contributing to an expanding pool of knowledge. This research investigates the use of semantic and social web technologies and Information and Communication Technologies (ICT) to facilitate public engagement in construction projects. The proposed framework features a core ontological model that is integrated with web-based middleware. It will contribute to the sustainability of construction projects through enhanced two-way communication and enriched public participation.

Over the last ten years, there has been growing interest in the implementation of knowledge management (KM) systems within the construction industry. The fragmented and transient nature of construction project teams makes the industry ideally suited to benefit from improved management of the knowledge generated in the course of construction projects. This paper is concerned with the evolution of knowledge management systems for construction. It starts with an exploration of the adoption of KM systems by construction sector organizations over the last decade and identifies some of the emerging trends. It also reviews some of the major knowledge management systems developed over the period and highlights the strengths and limitations of these systems in relation to what the industry needs. It argues for a new generation of knowledge management systems that are better suited to the dynamic, global and complex environment within which contemporary construction projects have to be delivered. The key features that such next-generation KM systems should have are also discussed and conclusions drawn on their significance.

This paper examines the embedment of a knowledge management (KM) program within an individual global engineering organization, Fluor Corporation (Fluor). Although many knowledge management initiatives fail, the program established by Fluor achieved increasing legitimacy and became a taken-for-granted practice over time. This paper examines the process of embedment by analyzing the changing use of the program through participant quotes. In addition, it identifies factors that contributed to the ongoing use and embedment of the KM program in Fluor's operations. These include the alignment of the program with Fluor's culture, the continued maintenance and ease of use of the program, social influence factors, and external changes that together evolved the KM program into a well-used, award-winning program around the world. This case study offers the rare opportunity to investigate a KM program that has been established in the AEC sector for almost a decade and offers insights and suggestions to firms seeking to implement knowledge management programs in the industry today.

Building Information Modeling (BIM) provides a means for owners, designers, contractors, and operators to generate, organize and use detailed information throughout a project lifecycle. When properly implemented, these models can improve the efficiency of designs, allow for better feedback from project participants, and improve the accuracy and effectiveness for performing future construction tasks. An important aspect to the success of BIM is the process in which information is exchanged. Information should be both accessible and usable when required. This paper serves to identify categories of information exchange (IE) waste on a building project through the application of lean theory. Using this methodology, a pilot study was performed on a laboratory facility being constructed on The Pennsylvania State University campus. The results determined that lean theory can be applied and adapted to effectively determine IE waste. Future work includes calculating the cost associated with this waste, and converting the waste into an efficient information exchange process.

The construction industry has been shown to suffer from poor productivity performance and a lack of innovation. One area where substantial improvement potential lays is subcontractor selection. Subcontractor selection strategies employed by contractors can significantly impact the success of individual organizations and the overall efficiency of the market. Long-term partnerships are promoted by experts from both academia and industry as a means of achieving improved project network productivity; however, opportunistic bidding behavior that may accompany its implementation has been largely ignored. We conducted a bidding experiment to simulate whether opportunistic behavior would emerge in the subcontracting process. The purpose was to observe whether the hold-up problem occurs as previous simulation research focused on game theory indicates. The empirical data was collected through an internet based interactive bidding simulation developed by the investigators. The findings contribute to the project management literature by empirically demonstrating how opportunistic behavior occurs in the bidding process and how it leads to different partner selection strategies by contractors and different market outcomes in terms of efficiency.

Nearly 200 interviews and surveys collected by a Construction Industry Institute research indicate that innovation is valued within large engineering-procurement-construction (EPC) organizations but is hindered by organizational factors such as lack of resources allocated to innovation efforts; low risk tolerance; and a failure to establish innovation-enhancing processes. To enable EPC organizations to evaluate and improve their innovation capabilities, the team created an Innovation Maturity Model (IMM) that evaluates an organization in each of 61 innovation-related attributes. The IMM, which is based on the data collected and a review of relevant innovation literature, includes a macro-enabled spreadsheet that aggregates the individual survey data, identifies the ten attributes offering the greatest opportunity for improvement, and provides the recommendations for improving these ten attributes. The IMM was pilot tested using six large EPC organizations and will be available through the Web.

Despite increasing industrial interest in Concurrent Design, little empirical research has been undertaken on design conflicts that occur during such concurrent engineering design efforts. To overcome this gap, this paper presents results from a case study we conducted at the Chinese office of a worldwide operating design consultancy firm. This paper presents the sources of conflicts that practitioners of this design office encountered during concurrent design activities on a number of historical and ongoing projects. The paper also presents a number of strategies to effectively detect and manage conflicts on concurrent engineering projects that we derived together with practitioners of the design consultancy company. These strategies include processes for effective change management, communication management, quality management, and risk management.

Three key aspects necessary to ensure a successful project environment are communication, coordination and cooperation (3Cs) between stakeholders. Incorporating these aspects into implementation strategies is paramount to facilitate project delivery and relationships among stakeholders. This paper reports results from a study on collaborative efforts between transportation agencies and tribal nations within the United States. Several methods were used in this study, including qualitative content analysis, workshops, interviews and a Delphi study. Findings include a list of issues that are encountered on projects affecting tribal communities, and a set of 3Cs strategies, which have been utilized to establish a collaborative environment. The study has implications for the architecture-engineering-construction industry because the singularity of the relationship between owners and stakeholders significantly affects several aspects of a project delivery, including planning, design, construction, and operations. These implications are summarized in the final section of this paper.

Research on governance of infrastructure projects has explored who should optimally own and operate these assets. Instead, we focus on a set of governance challenges that arise systematically during the project shaping, design, construction and operation phases of infrastructure projects. Importantly, project decisions at one stage can limit choice options and compromise financial, environmental and socio-political sustainability in subsequent stages. This paper discusses how these challenges arise within different phases of the infrastructure project lifecycle and propagate across phases; it shows how poorly traditional financing and governance approaches have addressed these challenges on past infrastructure projects; and it proposes socio-economic approaches that have the potential to address the governance requirements of future infrastructure projects more fully.

As the design and construction industry globalizes, firms are increasingly engaged in cross-cultural project networks that must share complex knowledge efficiently for projects to succeed. When complex design work is outsourced to international firms, researchers have shown that boundaries are created due to national cultural differences which can hinder effective knowledge transfer and reduce collaboration effectiveness. It is across these boundaries that knowledge system conflicts can occur. In this paper we longitudinally observe three complex engineering projects each involving a design firm in North America outsourcing a significant portion of the design work to an international engineering firm. Analyzing empirical interview data, collaboration meetings and project documentation we develop a model of knowledge system conflict emergence. We find these conflicts to arise in the initial stages of design collaboration. We classify the knowledge system conflicts into four categories; (1) linguistic, (2) scope of work, (3) work process, and (4) local knowledge. Understanding the emergence and typology of knowledge system conflicts that can occur on global projects can enable project managers to improve collaboration effectiveness on global projects.

Researchers have found successful collaboration that spans organizational boundaries enhances the productivity of the design and construction process. Researchers and practitioners alike argue using Building Information Modeling (BIM) should lead to tighter collaboration and closer communication among project participants working in cross-organizational environments. Using data from observations over fifteen months of the integrated design process of a laboratory building project, we build a typology of the strategies of successful collaboration within the AEC industry. Then, using interview data from 70 architects, engineers and general contractors from across the U.S., we test our proposed typology to suggest how the collaboration process is implicated in inter-organizational BIM integration. We find that inter-organizational BIM-enabled projects and successful inter-organizational collaboration have shared theoretical categories: fostering integrated teams; implementing tools and strategies to encourage clear communication across the team; and developing transparent technology use. We argue that attempts at either will not be successful without first establishing the right social and organizational foundation that supports both collaboration and successful technology implementation.

This paper introduces an agent-based simulation (ABS) of "the evolution of collaboration" within inter-organizational networks of construction project teams from a game theory and social network point of views. Our simulation shows that as individuals are less familiar with others in the network and thereby less aware of networks they are involved in, it is more likely to take a longer time for networks to reach stable states. It was also found that the stronger tendency of cohesion arises, as the effort that individuals have to make for forming a relation with outside partner increases. Furthermore, the results indicate that the more efforts individuals need to make to form relations with those from other organizations, the less efficient networks are formed.

Leadership styles of engineers were studied in a state organization, with the objective of making recommendations for improvement in decision making. A model was synthesized from a critical review of relevant literature, the underlying principles of which have found wide acceptance. Five styles were modeled in an outcome space — complete autocrat, impoverished manager, consensus manager, active manager, and consultative autocrat. The data collection process consisted of a questionnaire plus qualitative interviews. The research method included t-tests for the distance from the active manager's zone, and recording of trends and frequencies of qualitative data. Effects on styles were measured by variables such as years of experience and number of projects handled. Among the results, only one in twelve was an active manager, while more than 50% fell in the impoverished manager's region. The contributions contained ten recommendations that would take the organization to the next level by adopting a cross-section of motivational strategies.

This paper discusses an innovative approach for studying employee withdrawal behavior (e.g. tardiness, absence, and voluntary turnover). The traditional view is that withdrawal behaviors were caused by characteristics of the individual performing these acts (e.g., job dissatisfaction). While this view has received empirical support, an emerging view is that individual withdrawal behaviors are also governed by social forces within the job or organizational context. In effect, a culture emerges around these behaviors that effectively influence how individuals express themselves. Modelling these informal social dynamics, and understanding how individuals self-regulate within a dynamic social context, can be a great help understand this relationship between the two and further manage this behavior. In this paper we describe how this relationship has been approached in diverse literature and propose a feedback view on its understanding. Also, the implications of this research for management of withdrawal behaviors within the construction industry are discussed.

While the higher efficiency due to better pooling of resources is largely emphasized in Public-Private Partnerships (PPPs), the impacts of transaction costs embedded in PPPs are often understated. In fact, excessively high transaction costs could render PPPs an inferior alternative for providing public infrastructures/services. In literature, there are some studies examining the intrinsic types and sources of transaction costs embedded in different governance structures for providing public infrastructures. Specifically, two major sources of transaction costs in PPPs have been suggested, namely, the principal-principal problems and hold-up/renegotiation problems. This paper uses case study method to empirically examine the hypotheses concerning the transaction cost contingencies and whether PPPs are appropriate as a governance structure. The two cases are the Channel Tunnel project and the Taiwan High Speed Rail project, two of the largest and, yet, the most problematic and controversial PPP projects in the world.

Construction Manager-at-Risk (CMR) is an integrated delivery approach to the planning, design, and construction of civil engineering projects. CMR is well accepted in the building industry and is beginning to emerge as a viable delivery method for transportation projects. This paper correlates a comprehensive literature review documenting the advantages and disadvantages of CMR innovation with the output of 19 case studies involving structured interviews of project practitioners in the U.S. building, highway, airport, and rail transit sectors. The primary topical areas include the cost, scheduling, and quality aspects of CMR. The paper concludes that the innovations reported in the literature are not actually applicable to all types of projects. While the case study interviews confirmed at least one instance of each cited advantage, the primary innovation that can reshape construction practice lies in the constructability, biddability, and sustainability input that the constructor makes during the preconstruction services phase of a CMR contract. The paper recommends that owners leverage this advantage by carefully synchronizing both the design contract and the CMR preconstruction services contract.

There are a number of transportation agencies that have experience with accelerated construction strategies. California and Alabama have in the last several years completed major accelerated construction projects. These projects served as the proving ground for acceleration approaches and methods. When on two occasions a fuel truck collision damaged a bridge at the I-65/I-59 interchange in Birmingham, the Alabama Department of Transportation dedicated the necessary staff resources to accelerated project delivery under emergency conditions. Caltrans has had similar emergency projects both in rural and urban settings. This paper identifies, through a set of project case studies, construction operational and management practices that support accelerated project delivery. From this study it is evident that successful project acceleration is achieved through a partnering atmosphere and contracting methods such as design-build plus incentive/disincentive clauses that encourage a contractor to expend the planning effort and resources necessary to reduce construction time.

This paper proposes a fuzzy consensus approach that helps project teams in resolving conflicting responsibilities on their shared tasks in the Owner Managing Contractor (OMC) project delivery system. A list of shared OMC tasks is introduced to experts. Experts assign the responsibilities of project team members for every task using fuzzy preference relations on pairs of responsibility alternatives. Consensus degrees are computed for the preference values that are selected by the largest number of experts for the pairs of responsibility alternatives. The responsibility for each task is determined based on the pair of responsibility alternatives that receives the highest preference value. The approach is illustrated by a numerical example. This approach is relevant to the construction industry as it can be used to determine the responsibilities of project teams in the OMC or any construction project delivery system to ensure alignment between project teams prior to project execution.

Municipal water and wastewater facilities play an important role in the infrastructure of this nation. In a continued effort to provide such facilities, public owners have been using a variety of project delivery methods and contract pricing provisions for design and construction of facilities. The increased use of design-build project delivery with a guaranteed maximum price (GMP) contract pricing structure in the water and wastewater industry has created an opportunity to collect performance data to measure the effectiveness of these methods. Through a detailed survey of public water and wastewater facility owners, data were collected to compare project performance based on schedule and cost growth measures. Data were collected on 100 projects completed since 2003 and with a total price of at least $3 million. Results show that design-build projects have a greater intensity (cost delivered per unit of time), with no difference in quality from design-bid-build projects. Also, the results of this study indicate that contracts using GMPs are more likely than projects with lump-sum contracts to have no schedule or cost growth. Overall, the results of this study provide new data for water and wastewater projects that can be used by owners to improve future project performance.

Although public-interest ideals, such as transparency and efficient risk allocation, are widely recognized as crucial to well-structured public-private partnership (PPP) contracts, successful PPPs must also satisfy the public-policy objectives intended by the owner. Despite the pivotal role of toll-rate and concession-length options in shaping PPP agreements, relatively little research has addressed which of these contract strategies contribute most effectively toward achieving specific public-policy outcomes, such as managing congestion or limiting private-sector "super-profits." Various research methods are considered for investigating this topic. Acknowledging the limitations of traditional quantitative and qualitative approaches, this study proposes the use of configurational comparative methods (CCM). This family of recently-developed approaches is classified partway between quantitative and qualitative methods, enabling smaller sample sizes but retaining rigor and replicability. An example of CCM's application is presented, illustrating how this method can assist public-sector decision-makers in identifying PPP toll-rate and concession-length strategies which contribute toward achieving specific public-policy objectives.

This paper represents a step in a line of research aiming at mitigating the negative effects of conflicts on the construction industry through developing a construction legal decision support methodology. This step developed Support Vector Machine (SVM) models to automatically extract latent legal factors, upon which judges base their verdicts, from precedent cases. The adopted research methodology developed and compared the output of first, second, and third degree polynomial kernel SVM models while implementing 4 weighing mechanisms namely term frequency (tf), logarithmic term frequency (ltf), augmented term frequency (atf), and term frequency inverse document frequency (tf.idf). The models were trained and tested over two sets of Differing Site Condition (DSC) cases compiled from the Federal Court of New York. The two sets were composed of 120 and 450 cases respectively. The highest accuracy of extraction of 76% was attained using first degree polynomial kernel SVM while implementing tf.idf weighing with the first set. With the second set, a higher accuracy of 85% was achieved using third degree polynomial kernel SVM while implementing tf.idf weighing.

Billions of dollars are expended annually on maintenance outsourcing to preserve the existing highway network. Selection of the activities to be outsourced and the type of contracting strategy to implement primarily depend on the judgment of highway maintenance directors. While there are a large number of maintenance contracting strategies being used worldwide, maintenance directors often make their selections based on contracting practices they have used successfully in the past rather than by examining all possible methods and choosing an appropriate contracting strategy that meets specific selection criteria. In fact, there currently is no systematic method for choosing an appropriate maintenance contracting strategy. This paper contributes to the body of knowledge on the maintenance contracting selection process by summarizing 13 strategies being used worldwide to deliver maintenance services, identifying specific selection criteria that should be considered when making a decision, and presenting a decision framework that will aid highway maintenance personnel with the selection of effective maintenance contracting strategies.

In the construction industry, contractor failure is always possible. Surety bonding is a technique that is used to reduce the risk the owner may face in case a contractor fails to complete a project. When a surety company undertakes to provide a contractor with the bonding facility for a specific construction project, the risks of project completion are shifted from the owner to the surety company. A very complex qualification or assessment process is done to assess project specifics and contractual risks. There are many qualitative and quantitative factors that are taken into consideration, and some of these factors have a nature of uncertainty and subjectivity. The purpose of this paper is to present a methodology for developing a framework for formalizing the contractor and project assessment process to obtain surety bonds for specific construction projects. The framework includes the integration of multiple technologies (genetic algorithms, fuzzy logic, neural networks, and learning from examples) into a single application.

International construction projects provide opportunities for developing countries to advance in the global economy and for international firms to increase their profit and market share. Despite the attractive opportunities that international construction offers, there are many challenges and difficulties to moving into international markets. Many risks are associated with international construction, one of which is the risk arising from culture differences, and the way this affects how contract clauses are written. One of the very critical clauses affected by the cultural aspect is the dispute resolution clause. This paper discusses the different dispute resolution methods employed in international construction contracts and develops a model suggesting the use of specific dispute resolution methods depending on the culture characteristics. Finally, the model is used to develop testable propositions of the relationship between the dispute resolution methods and the characteristics of the culture studied. The propositions developed may eventually help in the selection of the appropriate dispute resolution method during contract formation.

This paper calls for a project partnering contract that integrates the entire project team under a single multi-party document. A three-phase methodology study based on literature review, interviews with 21 senior industry practitioners, and subsequent associated analysis was utilized in order to meet the goal and objectives of this study. Under this research, a series of principles and guidelines were highlighted whereby the owner, contractor, suppliers, and manufacturers collaboratively work together under the same terms and conditions. Thus, the owner has to deal with only one integrated contract which substantially reduces the risk of gaps or overlaps between the different roles and creates duties of care between all team members. A partnering contract would never, on its own, change the culture and environment of the construction process and thus, strategic partnering should be promoted not only at project specific activities but at all organizational activities. It is perceived that that this research would hopefully lay basis and foster legal professionals towards drafting of the first standard U.S partnering contract, which should help in developing a more effective and efficient contracting environment.

This paper describes the results of an implementation of a decision support system to aid analysis and selection of engineered equipment suppliers in the early stages of capital projects. Procurement of equipment is a complex process which requires the evaluation of multiple suppliers against project targets. This analysis is usually performed manually, is time consuming, and certain tradeoffs may be overlooked. A technique to support procurement decisions with complex tradeoffs among key variables has been missing. The results of this research take significant steps to fill this gap. The system integrates historical data, market assessment, and supplier bid information to support evaluation of tradeoffs among cost, schedule, quality, shop load, and transportation variables. Validation was performed with two recent selection cases. Data from commercial bid tabs was imported into the system and results were presented and compared against three EPC firms' final recommendations. The decision support system provides rapid evaluation and comparison of several supply alternatives, thereby improving the consistency and quality of commercial analysis in the early phases of capital projects.

Current construction practice is very fragmented and is built upon a culture of adversarial roles; the different processes are carried out by various stakeholders who are not contractually responsible to each other and who many times are brought into the project after all major decisions have been made. The information exchange between the different parties is very limited. Building Information Modeling (BIM) is a tool that can foster project integration on different levels, because it can facilitate information exchange, access to real time information, and information gathering among project members. One specific application that can demonstrate how BIM can be used to integrate the team, the processes and the project phases is the use of BIM for the scheduling process. This paper defines Architecture, Engineering, Construction, and Facility Management (A/E/C/FM) integration, describes how BIM can enable project integration using the specific example of scheduling throughout the project using a preliminary model that leverages the capabilities of BIM, not only for 4D visualization, but also to generate and manage the schedule.

Due to their complexity, construction contracts frequently encounter contract modification disputes, especially, the compensation claims for errors in the bills of quantities under lump sum contracts. The prevailing standard contract forms such as Joint Contracts Tribunal's Standard Building Contract with Quantities (JCT SBC/Q) often contain provisions for the adjustment of the lump sum price if there are errors in the bills. However, undesirable outcomes are often observed under current practice. By developing a game theory model, this paper investigates the contracting parties' strategic interactions and analyzes the differential efficacy of alternative legal principles of compensation for errors. Based on this model, we derive the legal principles that may reduce opportunism incentives and minimize transaction costs. The principles suggest that claims for error compensation should pass the test that the errors are not obvious ex ante to the eyes of professionals. Prevalent standard forms under which the compensation is granted regardless of the nature of errors violate the derived principles and deserve further investigation.

Direct work percentage based on work sampling of construction projects measures the effectiveness of labor utilization at the workface, often exposes excessive traveling and idle time in the execution of construction activities, and reflects, to a large extent, the soundness of detailed crew level planning. This paper presents the findings from a series of productivity studies that were conducted on 123 construction projects involving 69 general contractors in the Austin, Texas area during the period of 1972–2008. Analysis of these work sampling studies indicate that there is a slight decrease in the direct work percentage and a slight increase in support work ratio during the period of 1972–2008. However, this trend cannot be justified at a statistical significance level. Nevertheless, it is reasonable to conclude that direct work ratio has been stagnant over the last four decades. The average direct work ratio is around 45% in that period and direct work ratio shows no statistical significant difference among different types of projects. The research concludes that labor utilization at the workface indicates that craftsmen are doing productive work less than half the time that is being observed. It is recommended that contractors employ significantly greater planning resources to ensure a larger percentage of direct work.

The construction industry has experienced profound changes that have forced construction enterprises to utilize performance measurements to improve their productivity. Current performance measurement frameworks (such as the Construction Industry Institute [CII] Benchmarking and Metrics program [BM&M]) mainly focus on the project level. In addition, many construction companies apply company-level performance measurement frameworks (such as the Balanced Scorecard [BSC]) that fall short in addressing particular issues and do not give a multifaceted measurement. An exploratory research was conducted to build bi-level performance measurement framework to improve construction enterprises' productivity. The proposed framework consists of two subsystems: company subsystem and project subsystem. The company subsystem is organized around the Balanced Scorecard (BSC). The project subsystem is organized around the nine knowledge areas of Project Management Body of Knowledge (PMBOK). The configuration of the viable system model (VSM) is utilized to enhance the model's implementation. This formulation process was followed by a structured interview and a case study to highlight potential adoption of the framework. Results show that the proposed framework can be vital in improving productivity of construction enterprises.

Variation in construction task starting time and duration can impact overall productivity performance, yet their root causes often remain unclear. In this research, variation is defined as the difference between what was planned and what actually happened. This paper examines the variation in starting time and the duration of construction tasks while considering 50 productivity factors. The 50 factors were divided into eight categories: prerequisite work, detailed design / working method, labor force, tools and equipment, material and components, work / jobsite conditions, management / supervision / information flow, and weather or external conditions. A nationwide survey involving craft workers, foremen, and project managers was employed and serves to offer valuable insight on the causes and impacts of variation. The findings will help construction project managers and field managers identify the common risk factors, focus on the root causes of variation in planning phase, develop effective strategies to reduce variation, and improve project

One of the main entry barriers faced by U.S. construction firms for entering the booming Chinese construction market is the acquisition of accurate labor productivity data in China. The accuracy of labor productivity data can mean the difference between the success or failure of the construction projects. Due to the sheer diversity and complexity of international construction practices, minimal research has been performed on comparative labor productivity between U.S. and China. Research is currently being conducted to assist U.S. construction firms in competing in the Chinese market. The U.S. labor productivity data is obtained from RS Means while the Chinese labor productivity data is collected on-site in Chongqing, China (Chongqing is the largest and most populated municipality of China's four provincial-level municipalities). Comparative review of collected productivity data d will help enhance U.S. construction firms' competitiveness in the Chinese market and improve their project management capabilities in China.

Value management (VM) has been reported to be useful in reducing costs while maintaining or even improving the performance of a project. However, many potential users in the construction industry are reluctant to use VM because of a lack of tools to assess VM studies. This paper is to develop a proper measurement framework for VM studies in construction. The strengths and weaknesses of the existing measurement frameworks are reviewed in the context of VM. Thirteen factors which have major impacts on the performance of VM studies in construction are identified and a theoretical foundation is established based on these factors. A preliminary framework is developed to explain how the desired features could be achieved. The identification of the key performance indicators (KPIs) by a questionnaire survey is then presented. A detailed framework which consists of the measurement processes, data providers, weightings of KPIs and definitions of the scoring is then developed. Case studies, focus group meeting have been conducted to refine the framework.

Each year, occupational injuries in the construction industry disable many workers and accounts for the lives of others. The commonly used indicators to measure construction safety are reactive, or lagging. On the other hand, predictive indicators such as measures of safety climate reduce the need to wait for incident to occur. Safety climate, referred to as the people's perception of the value of safety in the work environment, has been measured in various industries including construction. This paper has reviewed 15 such surveys to find the emergent themes of the instruments used in construction industry. Using content analysis and constant comparison analysis to analyze the data, the authors examined the survey instruments to identify key terms that reflect the main safety climate themes. While this study is no way exhaustive, analysis on the thematic basis of the survey questionnaires suggest that common themes relate to implication of safety rules and attitude of the management.

It is noted that project success and project selection and their corresponding criteria and factors have been treated as two separate project management topics. Project success and project selection have not been related to each other yet, but according to our research, they share at least fourteen common traits. This paper seeks to identify the common overlapping themes, which can be used to form a new common model known as the "Integrated Construction Project Selection Process". The model, which is based on the level of success of a construction company's previous projects, uses this information in the company's multi criteria project selection process. As a result, the model enhances the level of project success when a company selects a project. This integrated construction project selection model will be of considerable value to both senior managers and general practitioners within the construction operational environment as it will enable the industry to draw benefits from an integrated approach rather than from two disparate systems.

The current global economic situation and its negative impact on major oil and gas capital projects in Alberta have made construction productivity improvement more and more important. This paper describes the findings of an ongoing research project, presents the most critical aspects that can improve productivity in the delivery of oil and gas construction projects of Alberta. In this study, we have surveyed professionals from owner organizations, EPC firms and construction contractors to identify factors for improving productivity on future construction projects. Industry recommendations for improving construction productivity are categorized and tabulated into 10 major areas. These areas are labour management, project front-end planning (loading) and workface planning, management of construction and support, constructability in engineering design, engineering management, communication, contractual strategy and contractor selection, government influence and modularization, prefabrication, pre-build in shops.

Due to the costs and hazards of field training on heavy construction equipment, a market has emerged for computer-based simulators that eliminate such risks involved in construction-equipment operator training. Systems endorsed and utilized by equipment manufacturers are also being adopted by independent equipment operator training schools. Although the potential for facilitating skill development is evident, proof of the principles that make for efficient utilization of these systems is still not found in the published literature. Careful experimentation on how these systems are used is needed to demonstrate both the successful acquisition of skills and transfer of those skills to the operation of real equipment. After reviewing the market and summarizing principles of learning applicable to the skill development required for operation of heavy construction equipment, this paper highlights how those principles should be embodied in the implementation of training simulators and summarizes an experimental investigation focused on excavator training.

The construction industry requires an ability to assess the organizational performance with respect to occupational health and safety and to identify areas in need of improvement. For this purpose, a model has been developed to evaluate a safety management program with an emphasis on organizational processes. The result is an organizational safety management maturity model based on the hypothesis that continuous improvement of the safety program denotes higher organizational maturity and greater safety performance. This paper presents the researchers' development of the model; its application in collaboration with practitioners; and a sample of results to date. The model was developed through a literature review of safety performance, safety culture, safety climate, and maturity modelling research. Validation of the model includes elicitation from occupational health and safety experts, and application of the model to a representative set (in size and expected maturity) of construction organizations. The validation and data collection processes are completed in collaboration with the New Brunswick Construction Safety Association and WorkSafeNB (regional government's occupational health and safety organization). Only sample results to date are provided, to demonstrate how the model can be used to focus on the larger opportunities for improvement with respect to the factor groupings of 1) management commitment, 2) policy and standards, 3) worker involvement and commitment, 4) hazard management, 5) equipment, materials, and resources, and 6) working environment, and within each factor grouping the management cycle steps of 1) plan, 2) do, 3) check, and 4) act.

In order to evaluate the productivity of a project or a group of projects, the estimate or the schedule of the project in hand should be compared to those of other projects of similar nature. In the absence of proper data and points of comparison within the organization, industry standards and metrics are usually used. The standard industry metrics commonly used for assessing the productivity of the engineering phase of construction projects are the ratio of engineering hours per quantity of designed elements and the ratio of engineering cost to total installed cost (TIC) of the projects. The research into the validity of these industry standards for projects with different sizes is very limited. The scope of this paper is to assess the validity of the existing industry metrics for engineering productivity by illustrating the effect of projects size on the expected values of these metrics.

While the U.S Construction industry is currently experiencing minimal shortage in craft workers, the shortages that existed prior to the current economic downturn are likely to return. Previous research argues that worker satisfaction plays an important role in retaining and attracting more workers into the construction industry. The authors previously presented a longitudinal study at the 2003 ASCE Construction Research Congress that examined construction worker characteristics related with satisfaction, including race, union status, education attainment, age, and worker preference from 1970s to 1990s. This paper extends those analyses along with investigation of work-life related characteristics (e.g. respondents' annual income and spousal employment) among U.S. construction workers from 1970s to 2000s, utilizing the General Social Survey (GSS) data. A comparison of these demographic characteristics between construction and other industries is made as well.

Reducing project duration is rewarding for both owners and contractors in any competitive industry. Fast-tracking strategies are the most practical way to achieve shorter project duration, although these strategies invariably impose additional risks and may negatively impact project performance. Despite all negative impacts, if the effect of applying fast tracking techniques on project performance can be theoretically and practically identified, monitored and controlled throughout the project, the fast tracking can result in better outcomes. The objective of this paper is to demonstrate a theoretical framework for evaluating and quantifying the impact of fast-tracking techniques on project duration and cost. The ultimate outcome of the research presented in the paper is to provide project managers with benchmarked fast-tracking techniques which assist them in effective and efficient utilization of fast-tracking techniques from the preplanning phase of the projects.

Construction and facilities maintenance projects involve a large number of people and tasks with resource constraints and precedence constraints. This paper presents a new approach to model this problem as a resource-constrained multi-project scheduling problem (RCMPSP) with cost minimization. The scheduling problem is first decomposed into two sub-problems: schedule generation and sequencing. For the schedule generation problem, an effective forward and reverse schedule generation (FRSG) method is developed to generate a feasible solution for a given valid sequence. For the sequencing problem, a novel complete local search with memory approach embedded with FRSG is proposed to find the solution which has the best objective value. The proposed approach has been tested on the benchmark instances. Computational results show that it performs very well in terms of both effectiveness and efficiency.

The Supply Chain Management (SCM) field of research has developed a valuable set of concepts and strategies for integrating the core competencies of suppliers into the production systems, a trend followed by the construction industry. Research into quantifying the effects of upstream suppliers on the production rate of construction projects has been very limited. Literature for the construction industry generally discusses how SCM concepts can be adopted, or what problems and challenges inhibit such adoption without providing a framework to consider supply chain problems in early stage project planning. No analytical approach has yet been developed to help quantify the impact of upstream supply chain problems on the duration of construction projects. This paper presents an analytical framework for incorporating supply chain issues into project's plan and therefore assessing the impact of those issues on project's duration. A construction project case study is also presented for validation purposes.

Temporary Traffic Control Plans (TCP's), which provide construction phasing to maintain traffic during construction operations, are integral component of highway construction project design. Using the initial design, designers develop estimated quantities for the required TCP devices that become the basis for bids submitted by highway contractors. However, actual as-built quantities are often significantly different from the engineer's original estimate. The total cost of TCP phasing on highway construction projects amounts to 6–10% of the total construction cost. Variations between engineer estimated quantities and final quantities contribute to reduced cost control, increased chances of cost related litigations, and bid rankings and selection. Statistical analyses of over 2000 highway construction projects were performed to determine the sources of variation, which later were used as the basis of development for an automated-hybrid prediction model that uses multiple regressions and heuristic rules to provide accurate TCP quantities and costs. The predictive accuracy of the model developed was demonstrated through several case studies.

The scale and complexity of capital intensive projects, along with the presence of multiple organizations and stakeholders with conflicting objectives, often cause expensive delays and cost overruns in such projects. This study develops a framework to measure the impact of organizational and stakeholder interactions on the performance metrics of the construction process of capital intensive projects. First, an inter-organizational network is developed to identify the key organizations involved in a specific project phase using social network analysis. Then, potential interactions between these key entities having a negative impact on the performance metrics of the projects are identified and simulated. A Monte Carlo simulation is used to identify significant interactions and to determine their overall impact on the time metric. Nuclear power plant projects, with a history of actual costs of more than 200% the estimated cost, is used as a test bed to verify and validate the research framework. The regulatory agency, the utility company, financing entities, designer and directly affected parties were identified as key entities for these types of projects. In addition, interactions between the utility company and financial entities were found to be significant.

Infrastructure capital projects are at the center of efforts to invest in the recovery of the economy, both domestically and internationally, and are seen as a primary growth engine of the construction industry today. Sadly, many of these projects are unsuccessful due to poor early project planning. Front End Planning (FEP) is a critical process for uncovering project unknowns, while developing adequate scope definition and a structured approach for the project execution process. FEP assists in identifying and mitigating issues such right-of-way concerns, utility adjustments, environmental hazards, logistic problems, permitting requirements and so on. This paper will outline ongoing research funded by the Construction Industry Institute (CII) focused on front end planning of infrastructure projects. This investigation, which includes input from domestic and foreign planning experts from over 30 organizations using as reference over 60 capital projects, provides an understanding of the critical issues that must be addressed during FEP of infrastructure projects. Critical success factors for FEP of infrastructure projects will be shared, including key planning process steps, along with guidance to practitioners involved in planning infrastructure projects.

Modular Construction consists of one or more structure units fabricated in a manufacturing plant away from the jobsite. In the building industry, prefabricated modules are normally completed with trim work, electrical, mechanical and plumbing installed. Previous studies have proved that Modular Construction provided many advantages to the built environment, including the reduction of need for workforce, the reduction of onsite Green House Gas (GHG) emissions, and the improvement of construction schedule and product quality; however the extensive demand of pre-project planning and coordination among members of cross-interdisciplinary professionals have significantly impeded the application of this technique. With the recent development of Building Information Modeling (BIM), these challenges could be overcome through the BIM platform. Through case studies the benefits and challenges of implementing BIM in modular construction are clearly identified.

Highway construction projects have direct impacts on adjacent businesses. The nature and the degree of impact depend on individual business characterization and project specific factors. The type of business is also a relevant factor in predicting the impact of transportation construction projects. This paper presents the results of research focused on developing an in-depth understanding of these relationships. The study includes project case studies of three transportation construction projects in Florida. Surveys were conducted with all adjacent businesses, which were combined with analyses of the business accommodation procedures employed by State Highway Agencies (SHAs) nationwide to provide measure the efficiency of present rules. The results include an analysis of differing priorities for different classification of businesses and development of design and construction management best practices to better accommodate businesses during highway construction. A pilot project that employed business accommodation principles devised in this research, and improvements to business accommodations observed were compared to cases where no measures were taken.

The ability to plan and manage cash flows is critical for the survival and long-term economic success of construction contractors. Profiles arise from the interplay of outflows, e.g. labor, equipment, and materials, and inflows, e.g. progress payments less retainage, which very in frequency and are subject to payment terms. Their complex zigzag shape was previously only modeled with simplifications. Approaches included discrete values at specific points in time; averaged S-curves, e.g. from regression; or envelopes of extreme values. Yet neither is suited for cumulative costs of variable schedule activities. This paper therefore describes how cash flow profiles can be flexibly and accurately modeled with singularity functions, which originated in structural engineering. Their components define ranges of behavior between cutoff values. Emphasis is placed on expressing common payment terms, which are illustrated with an example that is validated with the literature. This new approach augments project planning toward an integrated model.

Resources are productive agents on construction projects and are therefore of special interest in project planning. Algorithms use heuristic or evolutionary approaches to (a) allocate resources underneath an availability ceiling to determine the minimum possible project duration or (b) leveling resources of noncritical activities within the fixed project duration toward a smooth profile of an even workflow. However, adding one or several types of resources in histogram bins is scale-dependent, disconnected from the underlying schedule, and computationally inefficient, as any change requires a recalculation. This paper therefore describes how such profiles can be modeled with singularity functions, which have been applied to linear scheduling, as cumulative additions over time. An example demonstrates how the activities and their resources remain coupled during an optimization procedure, e.g. resource leveling. Resources are extracted directly from productivities of their activities. The new approach also allows defining mathematical expressions for specific desirable or available profiles.

Increasing demand for project completion in a shorter duration has led to various methods of schedule compression techniques, that a well known among them is fast tracking that refers to overlapping activities that normally would be done in sequence. Fast tracking (overlapping) can reduce the execution time of a project while at the same time can result in rework, extra costs and increased risks as evident by many construction projects. In order to limit the risks of fast tracking and to gain maximum advantage, a tradeoff between benefits and losses of activity overlapping is required. Such a tradeoff requires a systematic and practical approach. For this purpose an analysis has been conducted over the inherent nature of overlapping to develop a new framework for optimizing activity overlapping in construction projects. The main objective of this paper is to introduce such a framework and the hypothesis behind it. The paper will also include the theoretical justification of the suggested framework to verify that the framework can be both reliable and practical to be used by project managers to find the optimum overlapping between activities to reduce the negative risks including sources of cost overruns and time delays.

Multiple shifts are often utilized in construction projects to accelerate schedules. Despite its advantages, the utilization of multiple shifts in construction often suffers from a number of limitations including additional acceleration costs and productivity losses. This paper presents the development of a multi-objective optimization model for scheduling multiple shifts that is capable of generating optimal tradeoffs among (1) minimizing the project duration; (2) minimizing the project cost; and (3) minimizing the utilization of evening and night shifts. An application example is analyzed to illustrate the use of the model and demonstrate its capabilities in generating optimal schedules and labor utilization plans for the day, evening, and night shifts.

Construction logistics can be used by contractors to plan and control the efficient and effective flow of materials from the suppliers to their incorporation into the finished structure. This paper presents the development of a construction logistics planning model that simultaneously optimizes the decisions of material supply and site layout in order to minimize logistics costs that include ordering, carrying, shortage, and layout costs. New methodologies are incorporated in the developed model to represent the interdependencies between material supply and layout decisions as well as to measure the impact of these decisions on project delays. An application example is analyzed to highlight the capabilities and performance of the proposed model.

The traditional monitoring practice involves collecting actual quantity data, and comparing against a benchmark which represents the relevant planned data. The encountered well-known problem in monitoring is that the quality of the collected data is often subjected to great variation due to the variation in the reporting skills as well as the willingness to record data accurately. A potential technique to circumvent this problem is to conduct the comparison against multiple possible outcomes rather than a single-valued benchmark. The main objective of this research is to utilize the Statistical Pattern Recognition (SPR) technique to classify the work planned at specified cut-off dates during the planning stage and use the classification to monitor and evaluate the progress during the construction stage. The SPR technique generalizes a virtual benchmark to represent the whole project based on multiple possible outcomes generated at a given cut-off date. The generalization feature offers a potential tool to overcome the problem of variation in the quality of data collected. Patterns are constructed to encode work of the project at different cut-off dates. Finally, the SPR concept and technique proved its robustness to monitor and evaluate progress of construction projects based on the technique of Critical Path Method (CPM).

Right-of-Way (R/W) acquisition for highway projects is a complicated process that involves many parties. It is critical for project participants to know the main factors that determine the R/W acquisition schedule. This paper reports on a research project that studies the impact of inherent factors on R/W acquisition durations. The research uses ANOVA and correlation techniques to analyze the impact of 15 inherent factors on 14 different durations in R/W acquisition. Data from 13 projects in Texas with 172 parcels were collected. Among the 15 factors, Transitional Area, Acquisition Method, Ownership Type, Title Issue, Mapping/Survey Issue, and Exchange were found to have significant impact on at least 4 durations, including the Total Duration. Using results from the post-hoc tests, this paper presents quantitatively how R/W Acquisition Total Duration is different among levels of each of the significant factors. This research is believed to place an important stepping-stone in improving R/W acquisition and project development for highway projects through the better understanding of the critical factors and better forecast for R/W acquisition durations.

A new semiconductor facility project can take four years to build, install production tools and start manufacturing. With the current market competition, companies target facility completion within 18 months. Projects are typically planned using a traditional scheduling methodology where successor activities start when the predecessors are finished, resulting in zero float in the schedule. Any delay can have a domino impact on the completion date. Often during the 18 months facility schedule, the owner will continue to adjust their end date and facility scope due to market demand. These changes can modify the contract scope and schedule causing the project team to lose sight of the project priories and lower their efficiency, passing accountability to the owner. In order to increase accountability and focus on the correct priorities a Key Date Matrix (KDM) was developed. The KDM improves the communication between different project teams, identifying and re-sequencing scope, quickly defining risk between the execution schedule versus need date for the activities. This was demonstrated to increase contractor accountability as 98% of the planned schedule was completed on time.

As infrastructure ages, a significant portion of US capital expenditure is incurred for the renovation and retrofit of existing facilities. Renovation projects are complex, high risk, and involve extensive coordination and planning, primarily due to uncertain site conditions and continuing operation requirements of existing facilities. Early studies have identified innovative and emerging technologies that facilitate site investigation and align renovation and maintenance activities with business production and operation schedules. However, the selection of appropriate technologies in specific project and business environments remains a challenge. Particularly, there is no guidance for project teams who must incorporate the selected new technologies into scope management and project planning. This paper establishes a framework to guide project teams towards appropriate technology selection in renovation project planning. A decision model is developed to integrate the technology selection process into a widely used scope management tool, Project Definition Rating Index (PDRI). The model is specially designed and flexible enough to allow project teams to decide appropriate technologies according to various criteria, including cost, application area, and risk mitigation.

Using Public-Private Partnership (PPP) model, the governments can utilize the resources of the private sector for financing and development of the capital-intensive infrastructure projects such as highways. PPP Highway projects are subject to revenue risks due to the uncertainty inherent in future traffic projections. Hence, the private sector is often reluctant to engage in these high-risk investments unless the government shares a portion of revenue risk by providing support instruments such as Minimum Revenue Guarantee (MRG). Incorrect modeling of traffic uncertainty and poor choices of MRG and Toll Revenue Cap (TRC) thresholds leads to inappropriate risk-sharing between public and private partners. This may inhibit the government from utilizing the capabilities of private sector and reduce the government's flexibility in investing on infrastructures in the future. A model for finding the optimal MRG and TRC thresholds based on Real Options methodology is presented. It incorporates the concepts of risk-neutrality and computes the investors' risk profile under MRG and TRC. It can help private sector better analyze the financial risks of BOT projects and make proper entry decisions based on the support instrument provided. It can be used by government to avoid undervaluing PPP initiatives or granting unnecessary subsidies to investors.

Several (ICJVs) have failed achieving time, cost and quality targets because of lack of an appropriate risk assessment methodology. This paper focuses on the analysis of the different ICJV risk environments. The related risks are analyzed into country, operating, sociopolitical and financial risks and then identified and grouped into internal, project specific, schedules, and major contract clauses risks. A simplified decision support system (RAMSCO) is proposed that breaks down project risks into discrete phases systematically. At each completion phase, there is a decision point where the up-date risk assessment can be reviewed and forth-coming actions can be identified giving the user a decision milestone whether to proceed or not. RAMSCO directs users through indices to minimize ICJV failure chances and evaluates the project's overall risk based on factor weighted ratings obtained from published researches. Two case studies are used to demonstrate RAMSCO's potential value.

The construction industry consistently accounts for the highest fatality rate of all single-service industries in the US. In an effort to design effective safety programs, several studies have quantified the relative effectiveness of injury prevention strategies (i.e., safety program elements). These studies typically examine the effectiveness of safety program elements (e.g., inspections) in isolation. The objective of this paper is to describe a recent research study that aimed to evaluate the influence that various safety program elements have on the effectiveness of one another. Using the Delphi method, the cross-impacts of fifteen highly-effective safety program elements were quantified by determining the percent increase or decrease in effectiveness that each element has on the others. The results indicate that the most influential injury prevention strategies are employing a site-safety manager, upper management support and commitment, worker participation and involvement, safety and health committees, and a site-specific safety plan. The subsequent analysis can be used to better understand the synergistic effects that exist among various subgroups of elements and to strategically create the most effective safety program when resources are limited.

Fault tree analysis is regarded as a powerful technique for assessing system reliability. The conventional approach of solving fault trees is based on applying probability theory by assigning probability distributions to basic events and propagating the probabilities to calculate the overall probability of the top event. However, applying this technique, especially in construction projects, entails several difficulties attributed to the lack of sufficient data to estimate the probability distributions for basic events. Thus, risk analysts tend to assume probability distributions of basic events, which adds further uncertainty to the analysis. To overcome these difficulties, this paper presents a simplified approach in which basic events are represented by a possibility distribution, and the possibility distribution of the top event probability is calculated by applying fuzzy arithmetic operations. The method presented herein is demonstrated using a case study to quantify the probability of failure of horizontal directional drilling (HDD). The proposed approach is able to overcome the difficulties of using the conventional approach by relying on linguistic terms rather than assuming probability distributions for basic events.

Since most projects today operate on tight budgets, one way to ease the potential for variations from budget is to price Alternative Dispute Resolution (ADR) techniques as an insurance product, which allows the project participants to transfer the risk of incurring unexpected high ADR cost during construction phase to the insurance company. Despite this advantage, many factors are preventing project participants from investing in ADR insurance. For example, on an, expected value (EV) basis, self-insurance almost always appears financially better than insurance premiums because of the insurance company's underwriting expenses and profit target that are included in the premium charges. However, expected value calculations miss important effects of uncertainty on the participants. In this paper, we borrow utility theory and introduce subjective loss to represent the "risk-averse" attitude of project participants when facing uncertainty. A convex subjective loss function (SLF) is used to translate the impact of ADR costs into utility-equivalent terms. Then the expected subjective loss is translated back to an equivalent certain monetary loss. Comparison between this derived certain monetary loss and the loss from investing in ADR insurance shows that even with the expense and profit loading, there is still an opportunity for a mutually advantageous insurance policy. And this opportunity grows larger as the potential ADR cost increases. Also, a numerical example is presented to illustrate how to structure a subjective loss function for project participants. It is the authors' hope that this paper could help project participants answer the question in the decision-making process: would they rather try to budget for an unknown cost in a wide range, or pay for insurance and be certain?

Due to increasing U.S. energy demand, the Nuclear Regulatory Commission is currently reviewing permit applications for 25 new nuclear power reactors. However, the previous generation of nuclear plant construction was beset by significant cost and schedule overruns. Several researchers have identified "regulatory ratcheting," increases in retroactive regulations, as one of the primary causes of the poor performance of these projects. Regulatory ratcheting was enabled, in part, by the two step nuclear power plant licensing process (10 CFR Part 50) that required plants under construction to meet all current regulatory requirements before receiving an operating license. This two step licensing process has been replaced by a single step process (10 CFR Part 52). How will this single step licensing process impact project performance? This question is investigated using a dynamic simulation model of the technical and social feedback processes that impact U.S. nuclear plant construction. The research reveals that under 10 CFR Part 52 society's amplified perception of nuclear power risks can still drive regulatory growth leading to potentially significant cost and schedule overruns.

Recent trends in the international construction markets indicate a growing number of projects that require a long-term investment strategy on the part of a construction firm. Therefore, this changing market environment calls for businesses to shift their paradigm from individual projects with limited decision-making tasks to projects with long-term investments and complex decision-making issues. The majority of the latest studies on international market entry address decision-making models based on risk analysis. When a contractor ventures into foreign markets, the consideration of various financial circumstances that he faces poses certain inevitable limitations. Therefore, this study developed a model that is based on real option analysis and Monte Carlo simulation, and is capable of incorporating uncertainties in the market during the evaluation of the market development proposal and the financial evaluation. The model allows for integrative consideration of both market risk and private risk. Applying the proposed model is believed to offer reasonable support to construction firms with maximum accommodation of each market's circumstances.

Contractor selection is carried out in order to choose a competent and capable contractor to do the work. To help in this selection, baselines are established to ensure that the contractors have the required skills, resources, and abilities to execute the project. Contractor selection is a multiple criteria decision making wherein several criteria are required to be evaluated simultaneously. This paper proposes a decision-making model for contractor selection utilizing ELECTRE III modeling. The steps of ELECTRE III model include; estimation of concordance indices, estimation of discordance indices, estimation of credibility scores, performing distillation procedure, and performing complete ranking. To assess alternatives via ELECTRE III, three associated thresholds are defined which are indifference (q), preference (p), and veto (v). These thresholds produce outranking relations with an allowance for data uncertainly. The complete procedure of ELECTRE III modeling is described in the paper. The proposed model is generic and can be used as a tool to evaluate alternatives in several applications such as value engineering, optimum organization structure, and constructability analysis. It enables its users to define the criteria that are deemed important for evaluation. The proposed multiple criteria decision making is novel to construction can be utilized as a successful tool in contractor selection problem. A numerical example is presented to demonstrate the use of the proposed methodology.

Finding competent collaborators while executing construction projects overseas is of paramount importance for project success. The partner choice and project performance cannot be understood only from an economic viewpoint since it is constrained by the firms' embeddedness in social relations. Based on this premise, this paper provides not only a theoretical explanation of the impact of structural and relational embeddedness on firms' economic behavior and outcomes, but also empirical evidence by analyzing collaborative cases jointly performed by Korean construction firms working overseas during the past 18 years. Three conclusions are drawn. First, the inter-firm network has scale-free network properties. Second, the network retained endogamic characteristics in that a great majority of smaller firms had worked with only one large firm, forming strong subgroups. Last, there is plausible evidence of the impact of structural embeddedness as well as relational embeddedness on the level of profit.

Knowledge of concrete lateral pressure is critical for the economical and safe design of concrete formwork. Innovations in concrete mixtures and construction techniques are frequently implemented. As a result, frequent updating of the recommended theories in the ACI 347 standard for predicting the maximum lateral pressure has become necessary. Some important parameters, such as pore water pressure, cannot be fully represented in a small lab scale experiment. Thus, field studies on full scale placements are necessary. This paper reports on measurement methods used to collect data under field conditions in studies conducted by this researcher and others. The objective of the paper is to present the experimental approaches for the benefit of other researchers contemplating similar research.

Every month, Engineering News-Record (ENR) publishes Construction Cost Index (CCI), which is a weighted-aggregate index of the 20-city average prices of construction activities. Although CCI is increasing in the long-term, it is subject to considerable short-term variations, which make it problematic for cost estimators to prepare accurate estimates. The ability to predict CCI can result in more-accurate bids and avoid under- or over-estimation. We conduct time series analysis and develop a CCI forecasting model based on the Seasonal Auto-Regressive Integrated Moving-Average (SARIMA) methodology. SARIMA investigates the underlying characteristics of the CCI data and makes systematic forecasts. The predictability of the developed SARIMA model is better than the predictability of the ENR subject matter experts' forecasts. The developed forecasting model can be used to prepare more-accurate estimates for contractors and budgets for owners and reduce construction costs by better-timed project execution.

Many work-related risk factors can cause construction site hazards. As well, risk for the same trade can vary due to different combinations of inherently changeable construction site characteristics. However, construction safety management has been executed similarly to other industries without reflecting the unique characteristics of the construction industry. To address these issues, this paper proposes a risk assessment methodology that considers the risk influence factors of construction sites and the risk of trade. Through a literature review and expert surveys, this study extracts risk influence factors and develops a weighting system for their classification. Risk of trade is calculated based on frequency and severity of risk. By integrating risk influence factors and risk of trade, this methodology can determine risk according to specific construction site conditions, thus enabling more effective safety management.

Sustainable design and construction has experienced significant growth in recent years. The predominant system in the United States for specifying and evaluating sustainable construction practices and materials is the Leadership in Energy and Environmental Design (LEED) rating system as prescribed by the United States Green Building Council (USGBC). Currently, research is lacking as to how owners communicate specific sustainability objectives to designers and constructors. Furthermore, it is unclear what approaches owners utilize for differing delivery methods. This study examines 92 recent projects of varying delivery methods, collectively representing over $2.2 billion in vertical construction from 2006–2009. The objective is to determine current delivery and procurement trends specific to sustainability. A content analysis methodology was used to examine and codify specific language and techniques used in procurement documents for each project. This paper presents the resulting framework of four owner approaches for specifying sustainable goals: 1) sustainability by competition; 2) sustainability by specified level; 3) sustainability by qualifications only; and 4) sustainability by reference. Within this framework, trends are discussed across all delivery methods as well as trends specific to individual project delivery methods.

The healthcare industry is one of the most significant built environment markets today with over 120,000 buildings in the United States. In spite of the recent decrease in construction spending, it is estimated that healthcare construction will rise dramatically in the next 10 years. Therefore, there is a great opportunity for improvements to be made in this market segment. Healthcare facilities are amongst the most complex facilities to design, construct and operate. Green healthcare can enable improved clinical outcomes, lower operating costs, energy consumption and water use. Lean principles emphasize whole process optimization through collaboration, continuous improvement, elimination of waste and a focus on delivering the value desired by the end-user (patients). Patients are a very special category of end-users, and their needs and health are the highest priority. The complicated healthcare building delivery system can benefit from focusing on the value adding activities and eliminating the wasteful ones. Building Information Modeling (BIM) can be very beneficial for healthcare projects because of the complexity within the building systems in terms of indoor environmental quality, cooling and heating loads, and also the large quantity of medical equipment. This paper examines the synergies existent in the healthcare construction market segment in terms of greening strategies, lean principles and BIM during the programming and early design stages of a project to provide a combined benefit greater than the sum of their individual benefits. A conceptual model is presented to improve healthcare facility delivery. Additionally, a research plan for future work is outlined and explained, and conclusions are drawn.

Building facilities are a major part of urban infrastructure, as they provide shelter, living space, and service areas to accommodate human activity. Despite their great economic, cultural and historical importance, many studies have shown that buildings are sick, deteriorating and considered to be a major source of pollution. Lack of funds and mismanagement are the principle reasons for the unsatisfactory performance of building facilities. Maintaining a building is essential to keep it performing and functioning for a longer period of time. Despite the importance of the condition assessment (CA) stage in the asset management process, a literature review reveals that there is no building assessment framework that considers both physical and environmental conditions. The objective of this paper is to develop an integrated CA model that integrates both the physical and environmental aspects of buildings. This model provides an accurate, reliable, and sustainable framework capable of assessing a building from both physical and environmental perspectives. The framework is to be implemented and tested using data collected from experts as well as from operation systems for existing office buildings in North America. Details of the proposed framework and its implementation are presented. The research work in this paper assists facility managers and owner's organizations in administrating such buildings.

Excessive amount of human-made Green House Gas (GHG) emission in recent years has caused a major global warming problem; yet in the past two decades or so, their adversarial effects are better sensed and reported. The construction industry and its related activities are major producers of these emissions. Despite their contribution, there have been minimal efforts in effective and proactive sensing and visualization of these emissions. This paper presents a system for visualization of GHG emissions from construction equipments during the construction phase and its application in a real-life case study. A metamorphic representation of trees is used to further demonstrate the required number of trees to neutralize released GHG emissions. To that extent, a system for visualization of construction emission is implemented, and the perceived benefits and further developments are discussed. The paper concludes that visualization can be used as an effective tool to assist stakeholders and managers in monitoring and controlling the environmental impacts of construction activities.

Large quantities of greenhouse gases are emitted in producing and acquiring, materials and equipment for the construction, maintenance and rehabilitation of highways. The objective of this research is to quantify the life cycle emissions associated with different pavement designs, by applying existing life cycle assessment (LCA) methods that integrate process-level construction data. The research is based on two pavement rehabilitation and re-construction projects across the State of Michigan. Field inspector's daily reports and direct site observation were used to collect data pertaining to daily material and equipment usage, construction processes used, and site characteristics. The paper describes the collection and organization of the data, and the calculation of life cycle greenhouse gas emissions associated with each project. This is part of a broader research effort to integrate process-level construction data, and long-term performance of each pavement type in the life cycle assessment of environmental impacts associated with highway infrastructure. It will support decision-makers in public agencies such as a Department of Transportation in assessing and reducing the environmental impacts associated with highway construction.

Many innovative techniques and large policy measures have been introduced to reduce energy consumption. Despite the high ambitions and societal pressures, the adoption rate of energy measures is still low. Using adoption theories this paper provides a framework to analyse the adoption process of energy saving techniques in building processes. The stakeholders in the adoption process of energy measures are analysed during every phase of a building project. This framework is used to analyse four projects of a social housing corporation. The low rate of adoption of energy saving techniques can be explained by the large number and variety of stakeholders involved.

Construction management and project delivery literature is dominated by quantitative methods. However, recent research suggests that its project based and people centric nature requires adoption of additional qualitative methods. Owing to the mounting complexity in sustainable, high performance building projects and consequent increase in the requirements for optimized solutions achieved by interdisciplinary integration of project teams; an on-going research aims to determine the relation between project delivery methods and level of integration in the delivery process and their further effects on sustainable goals. The preliminary findings of this study show that qualitative methods lead to a deeper understanding of sustainable building project delivery. In the conducted structured interviews and surveys for data collection mainly from three project participants (i.e. owner, designer, and contractor) for each case study, disjunctions were seen within inter-participant responses and between the survey and interview of the same participant. The affected metrics in this process, which include owner's commitment, project delivery method, and integration in the delivery process, are presented in this paper.

The reduction of energy consumption is one of the economic necessities in the United States due to the depletion of fossil fuel energy sources in the world. Renewable energy, such as solar energy, has been increasing in use in residential buildings to lower homeowner energy costs. The construction industry is also contributing to the reduction of energy consumption of buildings by producing designs that are energy efficient and by constructing buildings with energy efficient materials, and mechanical and electrical equipment. This study collected data on energy consumption (electricity and natural gas), building characteristics, and energy use practices of 30 homeowners and their residences in Henderson, Nevada. Statistical analysis was performed to determine electricity and natural gas consumption for theses homes. The results showed that the annual electricity and natural gas consumption of these homes was close to that of the national energy audit record. The study also identified six factors that affected the annual electricity consumption of the homes. Additionally, it determined three factors that affected the annual natural gas consumption of the home. The findings of this research will be beneficial to homebuilders and homeowners interested in reducing energy consumption through design, construction and homeowner practices.

The construction industry is a constantly-changing market, thereby making suppliers direct their efforts to understanding and meeting owners' requirements. Recently, a significant change in the construction industry has been the increased interest in sustainable materials. Material selection has been identified as an area where designers and contractors can have a significant impact on the environmental performance of a building. This paper illustrates how a tool to measure the user-based assessment of product sustainability can be used to evaluate the contribution of qualitative factors on material selection. The objective is to develop an instrument that validates user's perceptions of product sustainability and evaluate the effect of sustainable characteristics in the purchasability of construction materials. A survey of design and construction students and practitioners is carried out to capture the factors included in the instrument. A Factor Analysis approach is used to validate user's perceptions of sustainability and to demonstrate the effect on purchase intentions due to the factors considered.

Contractors, architects, and owners are often unaware of the credits that are achieved under Leadership in Energy and Environmental Design for New Construction (LEED-NC) 2009 by following the local building and land development codes in Alachua County. An analysis of the Alachua County Codes provides were analyzed to evaluate the probability of achieving credit and prerequisite requirements under LEED-NC 2009. Three credits and three prerequisites are achieved through code. Ten credits and three prerequisites share intent and have support for achievement through following the codes. By following the 2007 Florida Building Code and the Alachua County Unified Land Development Code, LEED certification cannot be earned under LEED-NC 2009 without project exceeding code requirements. However, this study provides local construction professionals with a starting point for selecting credits under the LEED-NC 2009 system in Alachua County.

Cost and time are the traditional criteria for selecting heavy equipment for construction tasks. However, non-road diesel-powered construction equipment can have health and environmental effects. For example, particulate matter and nitrogen oxide emissions from diesel engines impact local air quality, carbon dioxide emissions lead to climate change, and diesel fuel consumption is a non-renewable resource. In addition, diverse materials are used for manufacturing heavy-duty construction equipment, which can also impact the environment. An environmental life cycle model of construction equipment including uncertainty was developed to select equipment combinations for tasks based on the environmental impact associated with the life cycle of the construction equipment in addition to time and cost. Selecting equipment for a task based on life cycle environmental impact is another criterion that may be relevant for construction companies seeking to reduce their environmental impact. Results of modeling alternative equipment combinations that can be used to accomplish an example construction activity are presented in terms of time, cost, and life cycle global warming potential.

This paper investigates a number of challenges related to making existing buildings more sustainable to meet the increased demand for green office, residential and retail space. Some of these challenges include integrating the owner and user requirements, determining and prioritizing the required modifications to reduce the gap between the existing conditions and the required green standard, and finally aligning the alternative options for sustainably retrofitting the building with the available capital and resources. In particular, this paper will investigate innovative approaches to studying alternative greening solutions for existing buildings by augmenting the traditional life cycle cost analysis method with principles from financial and real options. These techniques are investigated because they provide the owner with the flexibility to value different alternative solutions for their buildings under conditions of uncertainty especially those related to demand for green space, fluctuating cost of energy and the perceived savings in the building operation and maintenance costs after sustainably retrofitting the existing building.

The problem with electric motor-driven HVAC systems is high electric demand charges during on-peak periods. Although the peak demand for electricity occurs for a limited time, electric demand charges can often account for approximately half of the total air-conditioning bill. Hybrid HVAC systems have been proposed as efficient solutions to offset these charges. The hybrid HVAC plant employs a chiller combination powered by electricity and natural gas. It can be programmed to select the most cost-effective energy source. An innovative approach to evaluate the economic performance of hybrid HVAC systems is presented. This model is based on the Life Cycle Cost Analysis Methodology. Our model considers dynamic changes in gas and electricity prices and compares the overall benefit of hybrid systems with traditional gas or electricity systems. For predicting the future electricity and natural gas prices, the discount factors adjusted for fuel price escalation, by end-use sector and fuel type should be provided. In the proposed method, an increasing factor is modeled by a binomial lattice. By conducting a Monte Carlo simulation based on the binomial lattice the factor range for each period is obtained. One of Georgia Institute of Technology's chiller plants is considered as a case study. Through conducting a case study on one of the Georgia Institute of Technology's chiller plants, it is shown that the overall cost-saving benefit of hybrid systems is sufficiently large to justify the additional expenses

On-site waste management is considered as an important part of the sustainable construction process in any construction project. In fact, almost all Leadership in Energy and Environmental Design (LEED) projects require considerable effort in waste management as part of the requirement to obtain the LEED credits and rating. However, sustainable waste management is achievable only if the process is cost effective in addition to the underlying societal and environmental benefits. Planning on-site waste management process is essential to achieve economic benefits. However proper planning and execution is not possible without prediction of construction waste quantities linked to the project execution plan. The paper presents a novel method of grouping factors, thus reducing the number of variables for statistical analysis which requires for establishing relationships between quantity of waste and many factors such as labour, material and environmental related factors. . The research outlined in the paper considers the principles of "Activity Based Waste Generation" which enables the prediction of total waste from a project (i.e. cumulative waste from each of the activities). The presented methodology is part of the research on "developing a planning tool for construction waste management" which involves site monitoring, and data collections from several building construction projects in Calgary, Alberta.

The research and literature reviews in the recent years clearly noted the immense economical, social, and environmental impacts created by the construction waste. Many developed countries have developed strategies and mechanisms to reduce the landfill deposits of construction and demolition (C&D) waste. Many European countries and Japan have been practicing C&D waste management for a much longer period and have effectively increased the percentage of recycled and/or re-used wastes in C&D. Landfilling construction waste materials has been recognized as a threat to the environment, especially due to its impact on groundwater quality. In addition, many previous researchers have clearly noted the immense economical, social, and environmental impact created by the construction waste. It was noted that the amount of recycled and/or reused waste use in the Canadian construction industry is much lesser than many other developed nations. Canada recycles and/or reuses only 22% of the solid waste while Denmark recycles and/or reuses 95% of the solid waste. There are many green building rating systems and standards- such as LEED, BREEM, CASBEE, and GreenStar - in the world. The LEED standards are quite popular in Canada. Each rating system uses different methods and weights to analyze the sustainability in construction projects. Although many Canadian construction projects use the LEED `ratings' to assess sustainability, it does not have a broad focus on C&D waste. The need for comprehensive and integrated waste management mechanisms, technologies, rating systems, and policies is widely visible in Canada comparing to some European countries.

Although attempts to assess sustainable impacts have been made for specific building components in construction domain, the study of material supply systems has been neglected due to the difficulty of analysis. The research intends to apply a process-based approach in which the analysis is based on processes instead of resources to investigate sustainable assessment of material supply systems in the construction domain. As part of the pilot study, the researchers did a case study where a process-based approach is applied to investigate financial and environmental impacts of rebar supply systems in building construction. The main purpose of this paper is to demonstrate how a process-based approach can be applied and address the difference of process design of alternative supply systems while traditional product-based approach does not.

The Strategic Petroleum Reserve (SPR) represents an investment in energy that no longer serves its original purpose. Created by the United States as a response to energy insecurity and instability, the original goal for this reserve was the creation of a one billion barrel reserve to offset supply insecurity. This original goal has slowly changed downward to the point where today the reserve could be depleted within a year in a national security event. This paper proposes a change in this policy with a significant investment in the energy sector to develop the domestic shale oil fields. Concurrently, the paper emphasizes how the energy sector has long represented a significant opportunity for the construction industry workforce. From oil fields to conventional power plants and nuclear energy generation, the construction industry has benefitted from the energy sector. Today, the opportunity exists to continue this tradition and provide the construction industry with the next generation of energy sector workforce.

Under the fast-developing carbon trading market, the construction industry needs to mitigate carbon emissions from construction processes. Among various construction processes, tunnel construction produces a significant amount of carbon emissions, since it utilizes various types of high energy-consuming equipment. In order to identify and mitigate such carbon emissions of a tunneling project, it is required to reliably estimate carbon footprints of a tunneling project in the pre-planning phase. This paper presents the methodology for estimating the carbon footprints generated during tunnel construction processes using the collaborative tunneling simulation. A case study using this methodology shows that carbon footprints from a utility tunnel construction are significant compared with those from a building construction. In addition, the assessment of carbon footprints of the case study identifies the opportunities to mitigate such impact by supporting decision-making on equipment and operation plans in the planning phase and providing a control target level of carbon footprints in the execution phase.

While the need for sustainable practices in building projects is globally recognized, some construction stakeholders still demonstrate resistance in adopting sustainable practices. The general perception is that attempting to achieve sustainability will increase the capital cost of construction and can delay the schedule. In recent years, societal pressure and government incentives as well as practitioners knowledge and acknowledgement, have led many construction projects to pursue sustainability credits. In 2002, Canada Green Building Council (CaGBC) adopted the Leadership in Energy and Environmental Design (LEED) standard as a tool to evaluate the sustainability of construction projects. The main objective of this research is to generate a better understanding of LEED professionals' perception of the impact of achieving LEED credits on projects parameters such as cost, schedule and future value. A survey was conducted to clarify their position towards the impact of each of the 69 points in the early version of LEED-New Construction on project factors. The survey targets factors in its three phases — prior to construction, during construction and post construction. The results can assist in improving the evaluating systems and developing sustainability design tools in the future.

Transportation is the largest Greenhouse Gas (GHG) emitting industry sector in North America. Between 1990 and 2005, emissions in Canada's freight transportation caused by Heavy Duty Diesel Vehicles (HDDV) increased by 18 mega tons of CO₂ (Carbon Dioxide) or 84% equivalent. Although many factors contribute and while different options such as increasing fuel economy and substituting alternative fuel for reducing GHG emissions from transportation exist, little attention is given to reduce these emissions via behavioral changes. This research investigates lowering emissions in the construction industry through intelligent and optimized route planning. The task of concrete delivery from batch plants to construction sites was identified to estimate GHG emissions. An emission map in ArcGIS environment using the road network of the Greater Toronto Area (GTA) was developed and later implemented in a decision support tool that enables construction industry practitioners to estimate GHG emissions from concrete transportation before ordering concrete from batch plants. Since material cost, delivery time, concrete quality, and availability often are the main criteria for practitioners to select concrete batch plants, the developed work offers practitioners with a choice for the lowest possible GHG emissions during concrete transportation. Although a more sustainable concrete delivery becomes feasible using the developed approach, results demonstrate that ordering concrete from batch plant varies depending on the search criteria selected.