Journal of Construction Engineering and Management

Selecting an appropriate competition strategy in bidding is the ambition of most contractors. The multiple requirements of clients encourage contractors to consider other strategies to deliver additional benefits besides offering a low-price bid. Offering low bids will reduce contractors’ profits and potentially make development less attractive. Contractors need to understand their specific resources that generate competitive advantage and accordingly develop strategies to win contracts. This paper reports the findings from a recent survey on competition strategies in the Hong Kong construction industry. Thirteen typical bidding strategies, their used frequency in bidding, and their effectiveness for winning contracts of different types and between different groups of contractors are studied. The analysis of findings is explored to provide local contractors and clients with new insights into competition strategies in bidding.

While the critical path method (CPM) has been useful for scheduling construction projects, years of practice and research have highlighted serious drawbacks that hinder its use as a decision support tool. This paper argues that many of CPM drawbacks stem from the rough level of detail at which the analysis is conducted, where activities’ durations are considered as continuous blocks of time. The paper thus proposes a new critical path segments (CPS) mechanism with a finer level of granularity by decomposing the duration of each activity into separate time segments. Three cases are used to prove the benefits of using separate time segments in avoiding complex network relationships, accurately identifying all critical path fluctuation, better allocation of limited resources, avoiding multiple-calendar problems, and accurate analysis of project delays. The paper discusses the proposed CPS mechanism and comments on several issues related to its calculation complexity, its impact on existing procedures, and future extensions. This research is more beneficial to researchers and has the potential to revolutionize scheduling computations to resolve CPM drawbacks.

Sleep deprivation contributes to fatigue, which can have a profound effect on an individual’s wellbeing, work performance, and safety. To investigate this phenomenon, a study was conducted on a sample of construction workers on a large construction project in Vancouver, Canada. This paper reports on the results from the workers wearing an actigraph 24 h/day for a full week to precisely measure their sleep and rest. The results enabled sleep efficiency and mental effectiveness levels to be determined by correlating them to blood alcohol concentration levels. This allowed determination of increased risk due to inadequate sleep. It was found that workers fell well under recommended sleep requirement guidelines of 8-h sleep per night, which resulted in an increase in risk of accident of 9%. Although further work is needed to better understand the coping mechanisms of fatigue and how the resulting fatigue factor could be measured and managed, this study indicates that workers in the construction industry suffer decrements in performance and are at higher risk of accident at home and work solely due to inadequate sleep.

Construction workers (CWs) are the key and indispensable contributors to every construction project. Their psychological feelings greatly influence their behaviors and safety performance. To improve CWs’ safety performance in dangerous working environment, the current research aims to identify the various stressors affecting two types of stress of CWs (i.e., job stress and emotional stress) and to explore the impacts of the two types of stress on CW injury incidents in Hong Kong. Eleven stressors were identified through factor analysis: work overload, role ambiguity, lack of autonomy, unfair reward and treatment, appropriate safety equipment, optimism, interrole conflict, poor workgroup relationship, lack of feedback, poor physical environment, and unsafe environment. The results of correlation and regression analyses reveal that (1) among the two types of stress identified, injury incident of CWs was found to be affected by emotional stress only, (2) emotional stress is predicted by work overload, interrole conflict, poor physical environment, unfair reward and treatment, and appropriate safety equipments, and (3) poor workgroup relationship, work overload, and interrole conflict predict job stress of CWs. Based on the result, various recommendations are suggested to employers on how to minimize CW injury incidents.

Considerable attention has been focused on addressing construction health and safety risks in developed economies. Sadly, the same cannot be said of developing countries in Sub-Saharan Africa where accident figures are extremely high. The aim of this study is to examine the influence of the contextual environment within which Ghanaian construction small- and medium-sized enterprises (SMEs) manage occupational health and safety (OH&S). A questionnaire survey was administered to construction SMEs to better understand the health and safety management practices and associated problems followed up by field interviews to explore key issues identified by the survey. The results of the study highlight the institutional structure for implementing OH&S standards, prevailing economic climate, and extended family culture as challenges to the management of OH&S. The study identifies low literacy levels, low socioeconomic status of workers, owner/managers’ ignorance of their OH&S responsibilities, commitment to extended family obligations, and ineffective OH&S administration as key factors limiting the capacity of construction SMEs to manage OH&S effectively. The study concludes that effective institutional structure and an enabling socioeconomic environment are needed to enhance the OH&S performance of SMEs and advocates for more proactive OH&S management that take into consideration the work cultures of SMEs.

The use of modular construction has gained wide acceptance in the industry. For a specific construction facility layout problem such as site precast standardized modular units, it requires the establishment of an on-site precast yard. Arranging the precast facilities within a construction site presents real challenge to site management. This complex task is further augmented with the involvement of several resources and different transport costs. A genetic algorithm (GA) model was developed for the search of a near-optimal layout solution. Another approach using mixed-integer programming (MIP) has been developed to generate optimal facility layout. These two approaches are applied to solve with an example in this paper to demonstrate that the solution quality of MIP outperforms that of GA. Further, another scenario with additional location constraints can also be solved readily by MIP, which, however, if modeled by GA, the solution process would be complicated. The study has highlighted that MIP can perform better than GA in site facility layout problems in which the site facilities and locations can be represented by a set of integer variables.

Commitment planning reliability at an operational level is a key factor for improving project performance. In the last 15 years, the Last Planner System, a production planning and control system based on lean production principles, has improved commitment planning reliability in the construction industry. However, many construction decision makers continue to rely on their experience and intuition when planning their commitments, which hinders their reliability. The reliable commitment model (RCM) is proposed to improve commitment planning reliability at the operational level by using statistical models. RCM is an operational decision-making tool based on lean principles that supports short-term forecasting commitment planning using common-site information such as workers, buffers, and plans. RCM was tested in several case studies, demonstrating its production forecasting capabilities and its ability to help increase commitment planning reliability and improve project performance. RCM also supports workload and labor capacity matching decisions. RCM has the potential of becoming a useful production decision-making tool.

Construction simulation is the science of developing and experimenting with computer-based representations of construction systems to understand their underlying behavior. This branch of operations research applications in construction management has experienced significant academic growth over the past two decades. In this paper, the author summarizes his views on this topic as per his Peurifoy address, given in October 2008. The paper provides an overview of advancements in construction simulation theory as reported in literature. It then summarizes the key factors that contribute to successful deployment of simulation in the construction industry, and the key attributes of problems that make them more amenable for simulation modeling as opposed to other tools. The paper then provides an overview of long-term simulation initiatives leading to the next generation of computer modeling systems for construction, where simulation plays an integral role in a futuristic vision of automated project planning and control.

This note proposes an efficient and cost-effective construction method for longitudinally supported large span latticed shell structures, commonly used for storages of existing stockpiles such as coal, stones, etc. The method divides a latticed shell into several segments, each of them is constructed sequentially. First, one segment-width scaffold is built at the assembling end of the structure. Then one segment of the structure is assembled on the scaffold. Once completed, the segmented structure is slid toward the other end of the structure to allow the scaffold to be available for assembling another segment. By repeating the above procedure, the entire segmented structure will form the resulting lattice shells. In the note, this construction method applied to two long span shell structures is discussed in detail. Structural analyses for each of the two accumulative sliding constructions have been examined before the construction, together with some suggestions for future similar applications using the method. From this note, researchers may transform the mobile construction method to explore other construction methods and practitioners of this technology can apply this method more safely and properly.