Publications

The rate of innovation in construction equipment is measured by using two variables over a 30-year period, 1962–92: The number of new models introduced every year and the technological life of eight earthmoving equipments are considered in this study. The findings indicate that the rate of innovation in the construction equipment industry increased in the 30-year study period. The findings also suggest that these innovations are incremental in nature, stimulated by technological advances in other industries, but primarily driven by market forces. Technological advances are not confined to the industry that produces innovations. The mapping of the interindustry flow of innovations highlights that while construction companies play a predominant role in generating their own technological innovations, they are also heavily dependent on other industries, such as the construction equipment industry for the flow of technical system innovations. As such, the continuous and incremental innovations in the construction equipment industry are bound to act as a catalyst for the generation of technological advances in the construction industry.

Awarding a contract to a bidder who has unbalanced the bid may cost more money to the owner. An owner who determines that a bid has been unbalanced has the legal right to reject the bid. Although several models have been developed to detect unbalanced bids, some researchers still assert that the number of cases in which owners mistakenly identify balanced bids as unbalanced is too great to ignore. One of the reasons of this failure is the use of an inappropriate benchmark against which the offered unit prices are compared. In this paper it is argued that the use of the geometric mean of the unit prices provided by the bidders as a benchmark helps to obtain robust solutions and an advanced decision-making model is proposed in which the Information Entropy and VIKOR methods are used to detect unbalanced bids. The results obtained from an example project drawn from the literature demonstrate how owners may be misled if they use an inappropriate benchmark in detecting unbalanced bids. This study contributes to the body of knowledge by highlighting the negative impacts of using flawed benchmarks in this process, an area of research that is mostly ignored in the unbalanced bidding literature.

This paper discusses the findings of a study conducted under the direction and supervision of the ASCE Committee on Management Practices in Construction (MPIC) to investigate the expectations of the parties involved in the construction process including designers, general contractors, subcontractors, owners, construction managers (CMs), and educators, relative to construction managers' duties and responsibilities. Statistical analysis was conducted to investigate if consensus exists among the parties and to highlight the agreements and disagreements between them. The findings were compared against the findings of an identical study also commissioned by MPIC 10 years before this study was performed. This study raises awareness among project participants about the fact that they should reconcile their differences and have a common understanding of CM duties over all phases of the construction project since general agreement over CM duties makes CM scope negotiations all the easier.

Construction management has been in existence for many years. This paper reviews the graduate construction management programmes offered by departments of civil engineering in the US. The courses offered in such programmes are categorized and examined in twelve groups. The findings indicate that the most popular subjects are those related to laws, contracts, and specifications; planning and scheduling; and operations research methods. Also, it was found that programmes differed a great deal from each other in terms of the concentration of and emphasis on the subjects treated. It is concluded that a clearer conception of the disciplineis necessary both by educators and the industry for higher quality and more uniform graduate programmes in construction management.

Building design and construction require the collective effort of diverse project participants. The coordination performance of these project participants is important for effective management and needs to be assessed periodically. However, there is no uncomplicated quantitative way to measure coordination. Measuring coordination is cumbersome and time-consuming particularly during the project execution phase. This study proposes an easy procedure for monitoring the coordinative performance of project participants. The degree, betweenness, and closeness centrality measures of the project participants in a wayfinding signage project at a major airport construction project are calculated using social network analysis on the e-mail communication network between the participants. A centrality index is defined for each firm based on the average of these three centrality measures. The firm's coordination score is also calculated based on content analysis of the sent and received e-mails between the participants. The coordination scores are found to be highly correlated with the centrality indices. To define the coordinative role of a firm, its centrality index could therefore be measured easily using a simple software and only the number and direction of e-mails exchanged between

Construction management has become a vital aspect of the construction process over the years. This paper reviews the Master's programs in construction engineering and management (CEM) offered by departments of civil engineering in the United States. The findings indicate that only 20% of the American educational institutions, which offer accredited civil engineering programs, offer Master's programs in CEM. Most of the Master's programs in CEM constitute an effort to convey information to students on mainly six categories, namely, contract administration, project management, scheduling, equipment management, construction technology, and CEM research. It seems that the Master's programs in CEM do not differ much from program to program in terms of content. When the trends in course offerings are compared in 1982, 1996, and 2008, there seems to be minimal change except for the number of courses in project management that went up significantly while the number of courses in cost estimating went down. The trends in the remaining courses have been stable. Even though contents and trends in CEM programs appear to be relatively stable, there seems to be some variability in the concentration of the course offerings. Some CEM programs concentrate on some of the categories at the expense of other categories. A close relationship and a sound dialogue between construction educators and the industry are likely to lead to Master's programs that are in sync with the expectations of the industry.

The difficulties that are met in construction projects include budget issues, contractual time constraints, complying with sustainability rating systems, meeting local building codes, and achieving the desired quality level, to name but a few. Construction researchers have proposed and construction practitioners have used optimization strategies to meet various objectives over the years. They started out by optimizing one objective at a time (e.g., minimizing construction cost) while disregarding others. Because the objectives of construction projects often conflict with each other, single-objective optimization does not offer practical solutions as optimizing one objective would often adversely affect the other objectives that are not being optimized. They then experimented with multi-objective optimization. The many multi-objective optimization approaches that they used have their own advantages and drawbacks when used in some scenarios with different sets of objectives. In this chapter, a review is presented of 16 multi-objective optimization approaches used in 55 research studies performed in the construction industry and that were published in the period 2012–2016. The discussion highlights the strengths and weaknesses of these approaches when used in different scenarios.

Construction activities are strongly affected by the properties of the site. Site conditions direct the investment decision and development approach. Leadership in Energy and Environmental Design (LEED), the most widely used certification system around the world, covers site properties with two sections, i.e., Location and Transportation, and Sustainable Sites. These two sections in LEED v4 NC add up to 42 points, which corresponds to approximately 33.3% of the total points that a building can receive. Issues such as neighborhood development location, sensitive land protection, high priority site, surrounding density and diverse uses, access to quality transit, bicycle facilities, reduced parking footprint, and green vehicles that are treated in the Location and Transportation section have different priorities and implications in developing countries. Similarly, issues such as pollution prevention, site assessment, site development - protect or restore habitat, open space, rainwater management, heat island reduction, and light pollution reduction that are treated in the Sustainable Sites section are based largely on local practices and standards, and therefore offer different challenges. In this study, these two sections of LEED v4 NC are assessed relative to practices in developing countries. A comparative review of the topics is performed by means of a thorough literature survey. It is expected that the outcome of the study will provide guidance to professionals in selected developing countries towards improvement of the existing state and practices.

This paper introduces a contractor quality performance (CQP) evaluation model that measures the quality performance of pavement contractors. The model uses a modified quality function deployment model to support the quality performance measurement that is involved in multiattribute and multiparticipant decision-making and the Delphi method to deal efficiently with the uncertainties in the input data. State DOTs that are in the process of selecting a pavement contractor for a project would benefit from the CQP evaluation model because the system allows a client to expeditiously assess the quality performance of potential pavement contractors in their bidding list. A test case is presented to illustrate the functioning of the model. The model contributes to improve the quality of the nation's pavements because it enhances the contract administration procedures by reengineering the current contractor assessment, prequalification, and/or selection process within the owner organizations (state departments of transportation) by accentuating total client (both the road users' and the owners') satisfaction. The model helps to improve the state DOT's pavement project bidding system.