Journal of Construction Engineering and Management

This paper presents an innovative model for scheduling, resource planning, and cost optimization of large construction and/or maintenance programs that involve multiple distributed sites. The proposed distributed scheduling model (DSM) employs an information system to store data related to various work sites, activities’ optional construction methods, and available resources. The DSM also incorporates a scheduling algorithm that is resource focused, and maintains crew work continuity under any sequence of distributed sites. To minimize cost and meet project time and resource constraints, the DSM uses genetic algorithms to determine the optimum set of construction methods and the optimum routing order among sites. Details of the DSM formulation are presented in this paper and the benefits to municipalities and contractors are outlined.

Reducing both project cost and time (duration) is critical in a competitive environment. However, a trade-off between project time and cost is required. This in turn requires contracting organizations to carefully evaluate various approaches to attaining an optimal time-cost equilibrium. Although several analytical models have been developed for time-cost optimization (TCO), they mainly focus on projects where the contract duration is fixed. The optimization objective in those cases is therefore restricted to identifying the minimum total cost only. With the increasing popularity of alternative project delivery systems, clients and contractors are targeting the increased benefits and opportunities of seeking an earlier project completion. The multiobjective model for TCO proposed in this paper is powered by techniques using genetic algorithms (GAs). The proposed model integrates the adaptive weights derived from previous generations, and induces a search pressure toward an ideal point. The concept of the GA-based multiobjective TCO model is illustrated through a simple manual simulation, and the results indicate that the model could assist decision-makers in concurrently arriving at an optimal project duration and total cost.

Time compression is a widely accepted approach to improving customer service levels while minimizing total costs. However, few applications within the construction sector exist, especially in relation to the early stages of program development and design. These stages are of paramount importance because of the resultant ramifications on the total cycle time of the entire construction project, in the form of changes, rework, waste, and risk. Most applications of time compression focus on quantifying and removing nonvalue adding time from business processes. This is difficult for program development and the design stages of construction because most information sources are qualitative. As a result, a methodology has been developed to identify the key areas of potential improvement during these early stages. Collection of opinion data via semistructured interviews, questionnaires, and a workshop with a cross section of supply chain members has made it possible to quantify the potential improvements. The action research findings have been summarized into a time-compression model for the program development stages in the format of two interlinked cause and effect diagrams. These further emphasize the need for effective program development to minimize the risks of project overrun.

The construction industry is a very competitive high-risk business. Many problems, such as little cooperation, lack of trust, and ineffective communication resulting in adversarial relationships between contracting parties, are facing the construction industry. Partnering is perhaps one of the most innovative developments in delivering a project efficiently and reducing construction disputes. It provides a sound basis for a “win-win” climate and synergistic teamwork. Project partnering in the Hong Kong construction industry has gained in popularity since 1994. A number of potential factors contributing to partnering success have emerged and deserve further study. This paper presents a review of the development of the partnering concept in general and identifies critical success factors for partnering projects from the Hong Kong perspective in particular. Through a postal questionnaire survey geared toward project participants with hands-on partnering experience, the opinions of various parties—clients, consultants, and contractors were sought and evaluated in relation to partnering success factors. The relationship between the perception of partnering success and a set of success factors hypothesized in the study was derived using factor analysis and multiple regression. The results indicated that certain requirements must be met for partnering to succeed. In particular, the establishment and communication of a conflict resolution strategy, a willingness to share resources among project participants, a clear definition of responsibilities, a commitment to a win-win attitude, and regular monitoring of partnering process were believed to be the significant underlying factors for partnering success. Such an identification of success factors could well formulate effective strategies for minimizing construction conflicts and improving project performance.

Thermoset composites are types of advanced plastics that perform well in high temperatures and pressures, can achieve tensile strengths similar to carbon steel, and have suitable electrical resistance properties. Because of these characteristics, engineers are increasing their use in the designs of both mechanical and electrical products, thus increasing the amount of thermoset scrap material sent to landfill sites (estimated to be approximately 1.2 billion kg per year (920,000 t). As a way to reduce the amount of this scrap material taken to landfill sites, possible construction applications are being investigated. Using American Society of Testing and Materials standards, a better understanding of its material properties are being explored, such as strength, density, uniformity, chemical resistance, and impact resistance. One potential application, developed and tested for its suitability as a construction material, was as a flooring substitute for traditional ceramic tile.

The preparation of detailed models of information and process flow by 14 member companies of the North American Precast Concrete Software Consortium has provided a unique window into the current management, engineering design, and production operations in this industry. The modeling was performed using the authors’ Georgia Tech Process for Product Modeling tool, within the framework of the consortium’s effort to develop a precast concrete product model and to specify new integrated three dimensional modeling software. The paper opens with a comparative economic review of precast construction internationally and in North America, which reveals that the market share of precast construction in North American is relatively low. The models are analyzed and aspects of the underlying management procedures that they reveal are discussed, such as types of contracting arrangements, cost estimating, design outsourcing, engineering design communication, mold design, product diversity, and quality control. The results highlight aspects of precast management processes that may be re-engineered through appropriate application of information technology.

This paper focuses on the topic of data collection as appropriate for the productivity study of ready mixed concrete placing methods. Classification and description of various concrete placing methods are given. The normally available quality control (QC) records for 462 concrete pours from five ongoing Hong Kong building construction projects were captured into a database, representing a total of 6,833 truckmixer trips out of two major concrete plants in Hong Kong. By querying the database, the placing rates for particular placing methods were established, and validated by comparison with existing industry benchmarks. One promising observation is that in general the Hong Kong construction sites may now be more efficient in processing truckmixers than they were a decade ago. The normal concreting QC records, routinely accumulated on site in a mandatory and standardized fashion, include the timing and quantity data as needed because of the time-sensitive nature of freshly mixed concrete. Data of this type is a better and more convenient alternative to collection by direct observation and measurement. The concreting placing rates for the various placing methods derived from the database are found to be potentially of direct value for assisting concrete plant and site managers in estimating the progress of work and attaining better coordination in concrete supply and placing between concrete suppliers and site contractors. They also serve as performance yardsticks for benchmarking the state of the Hong Kong concreting industry as time goes by and indeed, and most usefully, for comparison with other large cities if similar records are obtained for processing from those cities.

Subsurface utility engineering (SUE) is a fast growing industry segment in the civil engineering arena. Subsurface utility engineering is gaining credibility as a significant tool to reduce the risk from informational uncertainty associated with underground facilities in a construction project. Subsurface utility engineering can minimize the risk primarily through mapping existing underground utility facilities, utilizing surface geophysical technologies, surveying and data management systems. This paper presents a comprehensive evaluation of SUE to facilitate a better understanding of this emerging industry by the many in the construction domain that are relatively unfamiliar with it. Topics investigated include quality levels in SUE, incorporation of SUE strategy at different stages in the construction project, and cost–benefit analysis of SUE based on 71 actual construction projects where SUE was employed. In addition, the results obtained from questionnaire surveys of State Departments of Transportation (DOTs) and the SUE industry are analyzed, which reveal the trend of state DOTs in the use of SUE and various aspects of SUE business in private sectors.

Various innovative public private partnerships (PPPs) have been explored in worldwide infrastructure development in which BOT (build-operate-transfer) is the underlying concept. Selection of the right concessionaire, which is critical to the success of such BOT-type PPPs, depends on the quality of identifying and defining suitable project-specific criteria and the quality of formulating an efficient tender evaluation methodology. A systematic research approach (including literature review, case studies, interview/correspondence, and a structured questionnaire survey) has been adopted to draw experience and learn lessons from international PPP practices and to unearth and refine experiential and expert knowledge from worldwide experts and practitioners. Tender evaluation criteria and methods currently used in diverse types of PPP projects in both developed and developing countries are identified, compared, analyzed, and then generalized.

Buyout is the transitional time between the preconstruction and the construction phases of a project. It is during buyout that purchase orders and subcontracts are issued. Most of the literature in construction addresses either estimating or project management but ignores the buyout time frame. This paper addresses how the buyout process attempts to reduce the ambiguities that occur during the transition from the preconstruction to the construction phase.

Maintenance management is becoming increasingly important in the building industry. Some of the reasons for this trend are: The large variety of uses for which buildings are constructed, the increase in the number of tall buildings, the increased use of electro-mechanical systems in buildings, and the higher performance of buildings. Because the financial resources for the maintenance of buildings and infrastructures are always limited, there is a need to find ways to allocate them among the various projects suggested for rehabilitation, renovation, and upgrading of existing buildings. The model developed in the present research to solve the problem of resource allocation is implemented in two stages, namely: (1) elimination of unfeasible solutions and (2) identification of five solution configurations that are close to the optimum. The model may be implemented in either of two ways: (1) maximization of benefits while adhering to a fixed budget or (2) minimization of costs while putting the emphasis on the performance of the buildings. The first approach is suitable for organizations interested in reducing the costs of maintenance. The second approach is suitable for organizations that wish to achieve the highest performance possible. The model developed was tested in a computer decision support system. The resultant solutions were evaluated using a large number of representative cases. The development of the model was finalized after subjecting it to sensitivity analyses. In this way, the effects of variations in conditions on the overall performance and costs were examined.

This paper presents a risk assessment methodology for underground construction projects. A formalized procedure and associated tools were developed to assess and manage the risks involved in underground construction. The suggested risk assessment procedure is composed of four steps of identifying, analyzing, evaluating, and managing the risks inherent in construction projects. The main tool of the proposed risk assessment methodology is the risk analysis software. The risk analysis software is built upon an uncertainty model based on fuzzy concept. The fuzzy-based uncertainty model is designed to consider the uncertainty range that represents the degree of uncertainties involved in both (1) probabilistic parameter estimates and (2) subjective judgments. Other tools developed in this study include the survey sheets for collecting risk-related information and the detail check sheets for risk identification and analysis. The paper finally discusses a detailed case study of the developed risk assessment methodology performed for a subway construction project in Korea.

More than 65 construction workers are killed each year due to trench related accidents. Accident prevention begins with having a clear understanding of the causes of these accidents. This paper discusses the analysis of 296 fatality reports related to trenching operations from the Occupational Safety and Health Administration (OSHA) in the 1997–2001 time frame. In this paper, two models will be considered to analyze the fatality reports and to find the major relationships between the “how” and the “why” of trenching fatalities. The first model considers the causes related to physical processes, and the second model evaluates causes that can be linked to human behavior. The understanding of the major links between these two models and other factors will help to develop more effective strategies to prevent trenching fatalities.

An organization must strive to maintain its most valuable resource, knowledge, in order to be more productive and competitive. One of the steps to manage the knowledge is to capture contents of the knowledge. In construction site safety, success in capturing the tacit knowledge of safety officers is of paramount importance; however without a good mechanism, this process might be difficult due to time and hazard perception constraints. This paper discusses research in a design-for-safety-process tool, which aims at: (1) capturing safety knowledge from safety engineers about construction safety hazards and the safety measures required; (2) assisting a safety engineer to identify safety hazards in construction projects and determine the safety measures required; and (3) training students and inexperienced safety engineers in identifying safety hazards and the measures required. In this paper, the first objective is discussed.

A survey of practicing professional civil engineers in the Australian states of New South Wales and Victoria was conducted. The survey explored the engineers’ experience of work and family sources of burnout. Burnout was predicted by a combination of both work and family stressors. Regression analysis revealed that burnout was predicted by different variables among respondents in dual- compared to single-income households and among parents and nonparents. Family variables were more important sources of burnout among participants in dual-income households and parents. The writer concludes that preventive strategies for burnout in the engineering profession must extend beyond the work environment and deal with issues at the work-family interface. Also, sociodemographic characteristics of the workforce must be considered when devising preventive strategies.