Journal of Construction Engineering and Management

Construction managers regularly monitor projects to ensure that the project performance is under control. The earned value method (EVM) is a widely used tool to forecast project cost and time at completion. However, the effectiveness of the EVM in forecasting schedule performance has been questioned particularly because of its inability to address the associated uncertainties and poor performance in predicting project duration. The objective of this study is to present an activity-based model to conduct a probabilistic assessment and estimation of schedule performance in repetitive construction projects. This model, called the Weibull evaluation and forecasting model (WEFM), emphasizes the recurring nature of major activities in repetitive projects to evaluate and forecast schedule performance. WEFM estimates activity completion time and its upper and lower bounds of possibility and presents these estimates in the form of prediction graphs. Moreover, it provides reliability graphs that demonstrate the probability of achieving a target completion time. The major contribution of this study is to utilize capabilities of the Weibull distribution in probabilistic evaluation and forecasting of schedule performance in repetitive projects. A numerical example, which demonstrates application of WEFM on four separate housing projects, underscores its adaptive nature and its advantages over the existing methods.

Time-related and cost-related waste through design and construction phases of the Green Building (GB) project delivery process are much higher than that of Nongreen Buildings (NGBs). Although prior studies have identified some waste types and related root causes for GB projects, a comprehensive classification of process waste and root causes encountered in GB project delivery does not exist in the literature. The objectives of this study are (1) to identify and classify waste types and associated root causes observed in design and construction phases of GB project delivery process, and (2) to rank the classified waste types and root causes based on their effects on time and cost increases during design and construction phases. To achieve the first research objective, an extensive literature review and a case study with three GB projects were conducted, and the identified root causes and waste types were represented in an Ishikawa diagram. To achieve the second research objective, two rounds of the Delphi method were performed with 12 panelists who are qualified in GBs and accredited by various areas of expertise. The findings include the following: (1) 6 major types of waste, and 4 types of primary root causes with 16 types of secondary root causes, (2) an Ishikawa diagram for representing the cause–effect relationship between waste and associated root causes, and (3) ranking of the identified waste types, and primary and secondary root causes in design and construction phases of GB project delivery process based on their significance. The contributions of this study are a comprehensive classification of waste and associated root causes for the GB project delivery process, a description of their relationships, and a ranking of waste types, and primary and secondary root causes in terms of their negative impacts on the GB delivery process in terms of time and cost. The findings of this study can be utilized for developing models and/or tools in the future that would allow the owners to detect existing root causes and potential waste in GB project delivery processes.

Unbalanced bidding is a common practice associated with both unit price and lump sum contracts. This practice is not usually in the owner’s best interests and is used in different forms by contractors for various reasons. Bid evaluation practices try to identify unbalanced bids and may reject the lowest bid if it is perceived to be unbalanced. Previous research on this topic focused on either helping contractors unbalance their bids or detecting imbalance in bids in order to reject them. This paper proposes a model based on a prevention, rather than detection, approach to handling unbalanced bidding. The proposed model balances all the bids submitted for a project and thereby neutralizes the impact of manipulating bid prices to obtain undeserved payments from owners. This approach protects the interests of the owners while maintaining the essence of competitive bidding by awarding the project to the bidder who submitted the lowest bid in a fair competitive process. Two examples, representing the bidding results of two projects, are analyzed to demonstrate the capability of the model in handling various forms of unbalanced bidding. Use of the model by owners will help protect them from the negative consequences of unbalanced bidding. It is also expected that, as owners begin to use the developed model, contractors will be less motivated to practice unbalanced bidding since it will not be possible to attain the desired objective by manipulating bid prices.

The process of assuring the procured and fabricated materials for an engineer-procure-construct (EPC) project are within their quality requirements is challenging because nearly every EPC construction project is complex and distinctive from previous projects in terms of its size, supply chain, and materials usage. In particular, EPC projects include contractors, subcontractors, and suppliers who collaboratively perform the engineering design for the project, procure the required materials and equipment, and then construct. Many (or most) construction organizations, representing owners and contractors, place high importance on documenting and tracking the quality performance of their suppliers as part of their sup plier quality management (SQM) to ensure that procured and fabricated materials are within the quality specifications. However, these organizations still face problems with their SQM, evidenced by the large number of rework tasks and replacement efforts for the supplied materials in the EPC projects. This highlights the importance of investigating the current supplier quality practices to explore effective practices to deliver products with the expected quality and zero rework. In this paper, six structured interviews were conducted with contractors, and 92 SQM documents including procedures and reports from 21 owners and contractors in the EPC industry were analyzed to identify the current practices used by these organizations with regard to SQM, and the most effective practices that construction engineering managers could borrow to improve the existing SQM in the EPC projects. The contribution of this research can be used by stakeholders in the construction industry to improve SQM within their organizations. Researchers can also benefit from this research to better understand SQM practices within the construction industry.

A major area of innovation within the architecture, engineering, and construction (AEC) industry involves the re-engineering of project delivery processes, yet successful implementation of such processes requires a significant organizational change effort. The AEC industry is often regarded as a laggard in the uptake of innovation, and personnel resistance to change is among the most commonly cited barriers to change adoption. The objective of this study was to understand the extent to which project level personnel change readiness is affected by a variety of antecedents within 16 AEC owner organizations, each of which independently implemented a planned strategic change in their project delivery processes. An outcome-oriented perspective of change readiness was incorporated to empirically document behavioral response to change at the individual level ($n=96$) among owner project managers and contracting officers. Change readiness outcomes were measured via an action research method in relation to contextual, personnel, content, and process antecedents present prior to change implementation on each AEC project. Results indicated that change management process factors of increased change message delivery and extensive change agent involvement had the greatest effect on outcomes of high change readiness. Individual experience and project scope considerations also had a relationship with change readiness, although to a far lesser extent. Contributions of this study include an empirical, multiorganization, real-time data set of change implementation within the AEC industry, identification of significant antecedent effects on personnel change readiness outcomes, and associated recommendations for change practitioners. Future research is recommended to investigate additional personnel-oriented characteristics of project teams and their corresponding relationship to change readiness.

There have been numerous research efforts to minimize construction defects and a variety of suggestions have been provided. However, while all of these suggestions are valuable and have the potential to prevent defects, a construction company may have difficulty adopting them due to financial and practical constraints. Thus, this calls for the identification and characterization of the most influential causes of defects, in order to prioritize defect prevention strategies. To address this necessity, this paper aims to identify the most important causes of defects in terms of frequency, magnitude, and pathogenicity. For this goal, a questionnaire survey of 106 industry professionals was conducted to examine 30 causes of defects, collected through an extensive literature review. High frequency and high magnitude causes were identified and traced back to their initiating causes. Accordingly, the five most pathogenic causes were found to be (1) organizational culture, (2) time pressure and constraints, (3) workplace quality system, (4) financial constraints on operational expenses, and (5) inadequate employee training or learning opportunities. This paper is valuable to researchers in terms of developing a theoretical foundation to analyze and visualize the complex mechanisms of defect generation in construction. Further, this paper is of value to practitioners in terms of providing an effective tool to set defect prevention strategies and prioritize investment areas for quality improvements.

Modern construction projects often include incentive/disincentive (I/D) provisions in order to serve a variety of different client objectives. Studies have shown both the advantages and disadvantages of using I/D clauses to improve performance. In India, out of 82 construction projects of varied size and nature investigated, only 14 projects of a critical nature were found to have I/D clauses in their contract document. The present study was carried out to identify various attributes affecting the successful use of I/D clauses in achieving their intended purpose. A total of 25 attributes were identified based on a literature review and structured personal interviews that present practical difficulties while using the I/D contracting method and thus, prevent I/D clauses from unlocking their true potential. These attributes have been evaluated based on the results of a survey conducted among experienced professionals working in the Indian construction industry. Factor analysis conducted on responses associated with important attributes identified five key factors: difficulty in contract management, additional effort by project participants, adverse effect on the working relationship of the client and contractor, increased responsibility of the client, and client’s reluctant top management. These factors also explain the reason behind the low acceptance of the I/D contracting method in developing construction markets. Case studies performed in four construction projects show that three out of four projects discussed were delayed due to inadequate understanding and wrong implementation of I/D provisions. This paper will be of interest to academicians and practitioners interested in the use of the I/D contracting method in construction projects.

This paper presents a smart artificial neural network (ANN)-based slip-trip classification method, which integrates a smart sensor and an ANN. It was trained to identify the slip and trip events that occur while a worker walks in a workplace. It encourages preventive and collective actions to reduce construction accidents by identifying the type of near miss, i.e., slip or trip, and the exact time that it occurs. The variation in the energy released by a worker is measured using a triaxial accelerometer embedded in a smart phone. This study is of value to researchers because the method measures a near miss quantitatively using acceleration. It is also of relevance to practitioners because it provides a computerized tool that records each and every moment of a near-miss event. A test was performed by collecting the three-axis acceleration streams generated by workers wearing a smart phone running the classifier as they walked around a simulated construction jobsite. It identified the type of near miss and the exact time of its occurrence. The test case verified the usability and validity of the computational methods.

Predicting the price of housing is of paramount importance for near-term economic forecasting of any nation. This paper presents a novel and comprehensive model for estimating the price of new housing in any given city at the design phase or beginning of the construction through ingenious integration of a deep belief restricted Boltzmann machine and a unique nonmating genetic algorithm. The model can be used by construction companies to gauge the sale market before they start a new construction and consider to build or not to build. An effective data structure is presented that takes into account a large number of economic variables/indices. The model incorporates time-dependent and seasonal variations of the variables. Clever stratagems have been developed to overcome the dimensionality curse and make the solution of the problem amenable on standard workstations. A case study is presented to demonstrate the effectiveness and accuracy of the model.

Traditionally, construction input is integrated after the completion of the design stage of the projects. Inadequate construction input at the predesign stage and during the front-end planning (FEP) process results in fragility of plans in terms of constructability. This paper reports on a research to investigate construction input during the FEP process. The research is based on three questionnaire surveys as well as complementary case studies. Questionnaires1 and 2 were developed to assess the status of the FEP process and select areas that require construction input, respectively. Case studies were then selected from a pool of projects and collected data were analyzed to investigate barriers to construction input. Results of the surveys and case studies suggested that lack of well-established interorganizational frameworks within project organizations, as a loosely coupled network, hinders effective construction input. Based on the results, a user-friendly decision aid, a construction input assessment tool (CIAT), was developed as a framework to facilitate, frame, and benchmark required construction input in the FEP process. Questionnaire 3 was then sent to industry experts to test and validate the tool. The results of the research (1) highlight the importance of construction input in the FEP process; (2) identify an application of structured frameworks, effective boundary objects, and established knowledge sharing at the firm level as facilitating factors to integrate the construction input in the FEP process; and (3) include a proposed tool that can be tailored and used in the industry to systematically facilitate construction input during the FEP process.

Previous studies agree that cooperation among participants is critical to successfully deliver projects; however, little research has quantitatively illustrated how participants benefit from cooperation. Based on partnering and cooperative game theories, the degree of willingness to cooperate (DWC) model has been used in this study to reflect the interactions among participants through dynamic simulation. With the support of data collected from a field survey, the outcomes of DWC model simulation have been tested, confirming that DWCs have significantly positive influences on cooperation gains, and incentives are effective in improving participants’ rewards. Application of the DWC model then reveals the cooperation status of hydropower developments in Southwest China, suggesting five practical strategies for interorganizational cooperation in project delivery. This study advances the knowledge area of multiorganizational dynamics during project delivery by building interdisciplinary linkage between partnering theory and cooperative game theory, which provides a structure to quantitatively unfold the cause-effect relationships between DWCs, incentives, and participants’ rewards. This research also reveals the mutual goals and different priorities of project participants and answers questions on how coalitions can be formed and how cooperation gains should be equitably allocated. The aforementioned findings can help practitioners to understand their positions in cooperation, make decisions to optimally integrate participants’ resources, and find ways to reach stable long-term partnering relationships.

Extremely large, complex projects with numerous geographically distributed stakeholders experience substantial risks related to the interfaces among stakeholders. This is particularly true during project definition and design, where despite discrete deliverables across the interfaces, decisions require some iteration. Managing interfaces has become feasible with the advent of internet and electronic product and process-management systems to the extent that full-time interface-management (IM) positions exist in practice. However, IM lacks formal structure, integration with critical-path-method scheduling, and methods to identify high-risk interface points (IPs). Throughout this paper, a graph-based algorithm is developed to identify key IPs in the network of IPs in a capital project. Furthermore, a new approach is discussed to link the key IPs to the interface milestones to identify schedule-related risks and mitigate their adverse impact. The functionality of the proposed algorithms is demonstrated in an offshore model project. The contributions of this paper provide foundational material for further research in IM.

Interface management (IM) is an emerging construction management practice that industry finds necessary for megaprojects that have become more complex and global. Defined as the appropriate management of communications, relationships, and deliverables among stakeholders, effective IM is integral to project success. Yet, because it is an emerging discipline, IM implementation has varied widely across the industry. Furthermore, the effect of IM on project performance is still unclear. To address these gaps, the construction industry institute (CII) chartered a research team, to identify the current state of IM and to investigate the relationship between systematic IM and project performance. To accomplish this, the authors conducted structured interviews for 46 projects. The study results showed that IM practices are most often found in industrial projects, with dollar values of more than one billion. In addition, IM adoption is positively correlated with the project dollar value and number of interface stakeholders. In terms of performance, projects with systematic IM tend to have lower mean and less dispersed cost growth, compared with projects without systematic IM. These results contribute to an understanding of the potential benefits of IM and its appropriate application as it further develops and is used in practice.

Electrical contracting firms have consistently pursued industrializing their business through the implementation of prefabrication, lean production, and supply chain integration. Despite the pioneering prefabrication efforts of electrical contractors, there is still no clear understanding of the determinants of electrical prefabrication feasibility in terms of supply chain collaboration and surrounding industry requirements. Accordingly, this paper presents the development of prediction models of prefabrication feasibility for electrical contractors. The research tasks of this study were performed in three main phases. The first phase included various data collection tasks, including conducting semistructured interviews, providing an online questionnaire, and obtaining relevant local economic data of the respondents’ metropolitan areas. The second phase involved the utilization of the collected questionnaire responses and economic data to develop logistic regression models that relate the prefabrication feasibility to its statistically significant determinants. The third phase involved validating the developed models by assessing their prediction accuracy and performing extensive sensitivity analysis of their determinants. The findings of this study should prove useful to electrical contractors who need to obtain data-driven assessment of prefabrication feasibility considering their business attributes and surrounding industry parameters. This study presents the two main contributions to the study field of construction prefabrication. First, prefabrication feasibility was found to be significantly dependent on four industry-related determinants: regional economic growth, industry competition, labor cost rate, and worker union resistance. Second, prefabrication feasibility was found to be significantly dependent on two main internal firm-related determinants: building information modeling capability and supply coordination with vendors.

Four-dimensional (4D) schedules have proven successful in planning with their visualization capabilities allowing for coordination and time-space conflict detection. However, when considered in depth, internal aspects of 4D scheduling techniques have not made significant advances from traditional two-dimensional (2D) scheduling. What is missing from 4D scheduling? Why has the interaction between activities, their relationships, and three-dimensional (3D) components not been flexible and adaptive enough? In light of these questions, this paper analyzes the current state of 4D scheduling. The missing element in 4D scheduling is found to be 4D relationships (4DRs). A prototype of 4DRs has therefore been developed to improve 4D scheduling. Finally, guidance on the application of 4DRs in 4D scheduling is presented to help the users come to a thorough understanding of its advantages and disadvantages and potential applications.

Aging buildings represent a significant percentage of existing buildings and are often in urgent need of upgrading to improve their operational, economic, and environmental performance. The owners of these buildings often seek to identify and implement building upgrade measures that are capable of improving building sustainability as well as achieving certification under various green building rating systems such as the Leadership in Energy and Environmental Design (LEED). In order to support decision-makers in promoting building sustainability and achieving LEED certification for existing building, this paper presents the development of a novel optimization model that is capable of minimizing the required upgrade cost of achieving a desired LEED certification level such as Silver or Gold. The model is designed to identify cost-effective building measures, plans, and/or performance to achieve a specified LEED certification for existing buildings while keeping required upgrade cost to a minimum. The optimization model is implemented using a genetic algorithm (GA) due to its capabilities of identifying optimal solutions for this type of problem in a reasonable computational time, and efficiently and accurately modeling this specific optimization problem with the least number of decision variables and constraints. A project case study of a rest-area building is used to illustrate the optimization model and to demonstrate its novel and unique capabilities. The primary contribution this research makes to the body of knowledge is its new methodology for optimizing the selection of building upgrade measures to achieve LEED certification for existing building with minimum upgrade cost.

The design–build (DB) delivery method has been widely used in the United States due to its reputed superior cost and time performance. However, rigorous studies have produced inconclusive support and only in terms of overall results, with few attempts being made to relate project characteristics with performance levels. This paper provides a larger and more finely grained analysis of a set of 418 DB projects from the online project database of the Design–Build Institute of America (DBIA), in terms of the time-overrun rate (TOR), early start rate (ESR), early completion rate (ECR), and cost overrun rate (COR) associated with project type (e.g., commercial/institutional buildings and civil infrastructure projects), owners (e.g., Department of Defense and private corporations), procurement methods (e.g., best value with discussion and qualifications-based selection), contract methods (e.g., lump sum and GMP) and LEED levels (e.g., gold and silver). The results show best value with discussion to be the dominant procurement method and lump sum the most frequently used contract method. The DB method provides relatively good time performance, with more than 75% of DB projects completed on time or before schedule. However, with more than 50% of DB projects cost overrunning, the DB advantage of cost saving remains uncertain. ANOVA tests indicate that DB projects within different procurement methods have significantly different time performance and that different owner types and contract methods significantly affect cost performance. In addition to contributing to empirical knowledge concerning the cost and time performance of DB projects with new solid evidence from a large sample size, the findings and practical implications of this study are beneficial to owners in understanding the likely schedule and budget implications involved for their particular project characteristics.

This paper aims to overcome the drawbacks of current business valuation models. The authors have developed a novel model, a growth value model, by employing the income-asset-hybrid-based approach and with the application of quantile neural networks. This model is greatly strengthened by the main assumption of stockholders equity growth rates following the mean reversion principle. This makes the discounted present value of stockholders equity in the infinite future converge to a bounded value. The empirical findings have significant contributions to the business valuation of property development and construction industries. First, they include the business valuation model of the aforementioned two industries is quite different from those of other industries. The enterprise values of these two can be significantly overestimated if the business valuation model for total industry is applied. Second, they also include the patterns of price-to-book value ratio (PBR) curves that indicate that the growth value model is highly useful and effective in various industries only if the return on equity ratio (ROE) is larger than zero.

In the construction industry, competitive bidding has long been used as a method for contractor selection. Because the true cost of construction is not known until the completion of the project, adverse selection is a major concern. Adverse selection is when the winner of the contract has underestimated the project’s true cost. Thus, the winning contractor will most likely earn negative or at least below normal profits. The winner’s curse is when the winning bidder submits an underestimated bid and is thus cursed by being selected to undertake the project. In the multistage bidding environment, where subcontractors are hired by a general contractor, the winner’s curse may be compounded. In general, contractors suffer from the winner’s curse for a variety of reasons including inaccurate estimates of project cost; new contractors entering the construction market; minimizing losses in case of recession of the construction industry; strong competition within the construction market; differential opportunity costs, which can affect the behavior of contractors; and the intention to win the project and then remedy the losses through change orders, claims, and other mechanisms. Using a game theory approach, this paper aims to analyze—and potentially reduce—industry exposure to the effects of the winner’s curse in construction bidding. To this end, the authors identify the degree of the winner’s curse in two common construction bidding environments; namely, single-stage bidding and multistage bidding. The objective is to compare the aforementioned two construction bidding environments and determine how learning from past bidding decisions and experiences can mitigate the winner’s curse. To this end, and through defining the relationship between the construction bidding and auction theory, the authors utilized a three-step research methodology that involved (1) presenting the symmetric risk neutral Nash equilibrium (SRNNE) as an optimal bid function; (2) developing simulation models for single and multistage construction bidding processes; and (3) analyzing the results of the simulation models, which is based on an actual dataset of projects provided by the California Department of Transportation. This research demonstrated that the majority of general contractors and subcontractors suffer from the winner’s curse in both single-stage and multistage bidding environments. Moreover, from a winner’s curse perspective, the multistage bidding environment incurs more losses than the single-stage bidding environment. However, through learning from past experiences, the multistage bidding environment provides contractors with a better opportunity to avoid the winner’s curse if compared with the single-stage bidding environment. This research should be beneficial for the profession to better understand the bidding decision-making processes. For future work, cooperative game theory can be applied with the integrated project delivery principles to help all associated parties mutually achieve their project objectives.

This paper presents the initial findings of an ongoing research effort focused on identifying, quantifying, and ranking essential industry practices for the successful delivery of faster fast-track, or Flash Track, projects. The research data collection involves literature search, engineering, procurement, construction industry interviews, and discussions with an industry expert panel. This research has extensively explored and analyzed U.S. and international practices and has deeply explored project execution practices in industries other than construction, including manufacturing, shipbuilding, and software engineering/development. The methodology employed in this research entails deployment of a three-round Delphi process and an Analytic Hierarchy Process to produce a comprehensive list of prioritized recommendations on essential Flash Track practices. This paper contributes to the body of knowledge by identifying and ranking 18 industry best practices essential to successfully manage the unique challenges and risks inherent in Flash Track projects. This research finds that planning, execution, and organizational practices are the most essential considerations for successful Flash Tracking. It also highlights the central role of trusting relationships and fully integrated work teams and, in doing so, extends earlier studies calling for innovative approaches, rethinking prevailing practices, and entertaining a new paradigm in Flash Track projects.

Decisions made before construction can affect safety on the construction site, either positively or negatively. This was observed from past research that identified the link between design decisions and fatalities. The concept of implementing design decisions that positively affect safety falls under the general concept of prevention through design (PtD), which attempts to identify and mitigate hazards early in the design process to eliminate the risks of injury or damage during construction. Prevention through design is practiced in other countries, primarily through legislation. The objective of this paper is to present the results of a survey that was conducted to identify construction industry stakeholders’ views on the concept of PtD and gauge the possibility for implementing PtD in the U.S. construction industry through either legislation or other means. Four distinct groups were surveyed: engineers, architects, contractors, and owners. Within this study, PtD was described and introduced to survey participants as design for construction worker safety (DCWS) to differentiate PtD efforts in construction from efforts in other industries. The survey consisted of questions that asked about the industry’s knowledge of PtD and the extent of PtD practice in the United States, participants’ opinions on designer and owner safety knowledge and perceptions, and obstacles and enablers for designer participation in construction safety. The responses from the various groups were compared to identify the groups that are more receptive to the idea of designer participation in construction worker safety. The results showed that architects were the least receptive to the idea, whereas the other groups were more likely to be supportive, with some hesitations. Architects and engineers identified the existence of economic, legal, and contractual obstacles for designers to practice DCWS, whereas contractors only identified economic obstacles. No enablers were identified by any group. The research contributes additional information that can be used by construction industry practitioners and organizations desiring to expand and optimize PtD implementation in the United States. The research results can be used by project teams to plan for PtD education and training efforts on projects and by construction industry organizations to develop PtD diffusion strategies.

Currently, there is no comprehensive benchmark of life-cycle assessment for the rigid pavement alternatives for highway rehabilitation. To fill this gap, the major objective of this study is to investigate the environmental, economic, and social impacts of the three most widely adopted rigid pavement choices through a life-cycle assessment approach with custom-built economic input-output life-cycle assessment (EIO-LCA) models. Quantity takeoffs were performed for each alternative assuming a 1-lane-km highway rehabilitation. Subsequently, the construction costs of each alternative were computed in order to determine the present values for a life span of 50 years, while at the same time accounting for a different life expectancy for each pavement rehabilitation strategy. The present values were then incorporated into a corresponding EIO-LCA model. The results clearly indicate that continuously reinforced concrete pavement (CRCP) is the most sustainable choice and much preferable to the other alternatives for minimizing negative environmental, economic and social impacts from the life-cycle perspective. This finding champions a wider adoption of CRCP for future sustainable transportation infrastructure development projects, as CRCP’s relatively high initial construction cost can be recouped by long-term sustained benefits. The results and findings of this study can serve as a solid foundation for industry practitioners and decision-makers to make better-informed project decisions when choosing the most sustainable pavement alternatives from a life-cycle perspective.

Contingency budgets are commonly used by managers to respond to uncertainty and control the project within the original cost and schedule targets. However, a variety of project participants with conflicting interests creates tensions when it comes to managing the risk contingency escrow account during the project development, and divergences often arise over the need for either retaining the unspent contingencies (for future risk and improved facility) or releasing it as a profit. With the purpose of studying the dynamics and main influences involved in the risk contingency management process of a design-build (DB) project, a system dynamics (SD) contingency management model is proposed to simulate the decision-making scenarios, under different project conditions and behavioral pressures of senior managers and owners. The model suggests that an aggressive proactive risk management practice might be an effective policy for managing the contingency budget in a complex engineering, procurement, and construction (EPC) project.

Cost-estimation participants play an essential role in the success of construction projects, as well as determining the profit margin of an organization. However, these participants must always work to rigid and urgent deadlines, putting them in stressful situations. Such a stressful environment influences estimation participants’ perceptions of the project and organization, which ultimately affect their performance. This study sets out to investigate the complicated relationships between stress, commitment, and performance for construction estimation participants through a questionnaire survey. A reliability test, correlation analyses, and regression modeling were applied to analyze the data collected from 101 construction estimation participants. The results indicate the impact of stress on both commitment and performance: (1) objective stress influences career commitment via an inverted U-shaped relationship; (2) subjective stress is linearly related to both career and continuance commitment; and (3) subjective stress also directly influences ineffective working processes through a U-shaped relationship. Other results show a separate and direct impact of the three types of commitment on different kinds of estimation performance: (1) affective commitment reduces ineffective working process; (2) continuance commitment exerts positive impact on organizational nonbelongingness; and (3) career commitment improves estimation accuracy. To optimize the performance of estimation participants, organizations are encouraged to monitor their abilities and arrange their workload accordingly, provide suitable support and assistance, and help staff formulate a long-term career development plan.

The applicability and effectiveness of case-based reasoning (CBR) have been demonstrated in various construction management areas, including bidding, international market selection, safety hazard identification, construction litigation, and preliminary cost estimation. Despite its strong potential as a decision-supporting tool in construction, only a few studies have applied CBR for estimating the preliminary duration that is necessary for the overall success of a construction project. Based on this recognition, this paper develops a CBR model capable of accurately estimating the construction duration in the preliminary stage. The applicability and effectiveness of the developed model are tested through application to 83 multihousing projects. The test results confirm the strong potential of CBR to provide an accurate estimate of construction duration with limited information available in the preliminary stage. This paper is significant in that it provides practitioners with a reliable decision-supporting tool for accurately estimating construction duration, and thus, ultimately increases the possibility of successful project execution.

Public opinion is becoming increasingly involved in feasibility studies, construction, and post-evaluation of large hydro projects. Recently, with the rapid development of social network services, sentiment analysis can provide officials and managers with fresh perspectives on public-relation problems in project management. An effective sentiment analysis method can enable projects to gain from public participation. In this paper, a project sentiment analysis (PSA) system using a lexicon-based method is proposed. This system collects user opinions from social network sites, establishes emotion dictionaries, and builds basic rules that calculate those sentiment values embodied in a collection of messages. The Three Gorges project (TGP) was used as a case study for demonstrating the effectiveness of the proposed PSA. Sentiment analysis results show that about half (47.7%) of the collected messages expressed negative emotions towards the TGP, while the other messages were positive or neutral. The case study is of help to Chinese government and project managers in future decision-making regarding the TGP. The PSA system provides a new theoretical perspective and a practical method to assess public opinion during the whole life-cycle of a large hydro project.

A roadway expansion that takes place on soft ground is susceptible to differential settlement because of the high consolidation of soft soils. Therefore, steps must be taken to lessen the risk of such settlement; yet, this often only results in costly drainage solutions. In that, applying a systematic value engineering (VE) process can be beneficial to develop cost-effective design alternatives. However, VE studies specifically targeting for this problem are absent from the field. Thus, the goal of this study is to supplement this knowledge gap by applying a systematic VE process to an expansion project on soft ground to demonstrate the benefits of performing VE. A case study was performed on an expansion project over a soft soil layer approximately 50 m thick. Through the VE process, the original design was reviewed, problems were discussed, and three alternatives were proposed. Then value analysis techniques were applied to evaluate these alternatives in terms of cost saving, function improvement, and value improvement with respect to the original design. The VE process and design alternatives as applied in this study are expected to serve as a guideline for engineers and decision-makers in roadway expansion projects on soft ground.

Design teams must make numerous decisions in building design, including choosing materials. Lately, they have become more concerned about the social and environmental effects of their choices, in addition to the economic constraints. These concerns, in addition to the increasing offerings of construction materials and products and the engagement of more stakeholders, make decisions more complex. As decision complexity increases, so does the need to systematically use sound decision-making methods. However, in practice many decisions are made without a formal method or discussion, thereby often generating conflict and waste in the design process. Further, even if practitioners are looking for better decision-making methods, the literature does not provide enough support for them to choose the best method for this context. This research fills the literature gap and provides a systematic approach as well as practical advice for decision makers by demonstrating the application of a method, called choosing by advantages (CBA). CBA creates transparent and collaborative environments in which to make decisions. To illustrate the use of CBA, this paper provides a detailed example of choosing materials, in this case ceiling tiles, in a commercial interior design project considering global supply chain issues. This paper contributes to the body of knowledge by illustrating how to use CBA for (1) integrating multiple perspectives, (2) identifying relevant sustainability factors, (3) making transparent trade-offs, (4) documenting a decision rationale, (5) separating value from cost, (6) organizing location-dependent factors, and (7) incorporating supply chain issues. CBA is a method worth adding to the toolbox of design teams determined to chose globally sustainable materials.

Notwithstanding technological advancements, construction continues to be a labor-intensive industry, and labor productivity remains the industry’s predominant determinant of performance. Numerous factors influence labor productivity, but buildability is among the most significant. Nevertheless, one of the barriers, and perhaps the most important to the implementation of the buildability concept, is the difficulty in measuring its tangible benefits to the construction industry; hence, the dearth of quantitative related research reported in the literature. Using a practical approach, this study has determined the relationship between relevant buildability factors and formwork labor productivity of building floors. The intermittent observation technique was applied to collect the data from 72 residential, office, and commercial buildings located in Kuwait. The factors explored included (1) variability of beam sizes in the floor, (2) usable floor area, (3) number of beams used to support the floor area, (4) number of individual slab panels formed within the floor due to beam-framing plan, (5) number of joints formed due to beam intersections, (6) floor configuration repetition criteria, and (7) number of angles formed around the floor perimeter. The relationship between each factor and formwork labor productivity was modeled by the categorical regression method. The results obtained show significant effects of the factors investigated on labor productivity, which substantiate the importance of applying the buildability principles to the design stage of building construction. The findings not only provide designers with feedback on how well their design schemes consider the requirements of buildability, but can also prove advantageous to construction managers for effective activity planning and efficient labor utilization.

This study investigates whether existing residential buildings can be repaired and maintained with alternative mixes of materials to maximize social, economic, or environmental benefits through a case study of a residential building repair and maintenance projects in Hong Kong. Based on optimization techniques, through a portfolio of materials two of the three objectives in building maintenance works can be achieved: employment generation, lifecycle cost reduction, and carbon emission reduction. These materials are different from the original ones used in the floors, walls, ceilings, waterproofing, and doors. The findings enhance the sustainability performance of the global building construction sector in overcoming the universal barriers to implementing energy-efficient buildings, namely, high initial cost, weak enforcement of government policies, and uncertainty of returns. The prototype model suggests that a portfolio of materials can be constructed to achieve two objectives at any given time, with the third objective acting as a constraint. The optimization techniques enable the global building construction sector to strike a balance among economic, social, and environmental benefits and constraints in maintenance works.