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There are various methods offered in construction literature for determining the schedule impact resulting from delays and interruptions. Previous scheduling technique makes the assumption that the relationship between time and the number of units produced is linear. Accordingly, progress is assumed to be equally distributed along the activities' durations. Often this assumption does not reflect the real situation for the progress of construction activities. Some activities are naturally nonlinear and others exhibit nonlinear progress. To insure reality and reasonableness, delay analysis must allow for nonlinear production rates as well as linear production rates in the delayed activities. Therefore, there is a need for a delay analysis method that incorporates the varying rate of production for the delayed activities. This paper proposes a delay analysis method that can rationally apportion the concurrent delay with consideration of the nonlinear production rates of activities in construction projects. A simple case study has been implemented to demonstrate the accuracy and usefulness of the proposed delay analysis method. This research is useful for both researchers and practitioners for the case including the varying productivity due to delays and interruptions and allows transparent and rational analysis on concurrent delay to facilitate claim analysis. Key words: claims, critical path method, delay analysis, productivity, scheduling. La litterature sur la construction comporte diverses methodes pour determiner l'impact sur l'horaire engendre par des retards et des interruptions. L'ancienne technique d'ordonnancement presumait que la relation entre le temps et le nombre d' unites produites etait directe. Ainsi, le progres est presume etre distribue egalement entre les durees des activites. Mais souvent l' hypothese ne reflete pas la vraie situation du progres des activites de construction. Certaines activites sont naturellement non lineaires et d' autres progressent de maniere non lineaire. Pour permettre sa fiabilite et sa raisonnabilite, l' analyse des retards doit permettre des taux de production non lineaires aussi bien que des taux de production lineaires dans les activites retardees. Ainsi, il faut une methode d'analyse des retards qui incorpore le taux de production variant dans le temps pour les activites retardees. Le present article propose une methode d'analyse des retards qui peut repartir de maniere rationnelle le retard concourant en tenant compte des taux de production non lineaires des activites des projets de construction. Une simple etude de cas est presentee pour demontrer la precision et l'utilite de la methode d'analyse des retards proposee. Cette recherche est utile aux chercheurs et aux praticiens dans les cas comportant une productivite variable en raison des retards et des interruptions et elle permet une analyse transparente et rationnelle des retards concourants afin de faciliter l' analyse des reclamations. Mots-cles : reclamations, methode du chemin critique, analyse des retards, productivite, ordonnancement. [Traduit par la Redaction], Introduction Delays and suspensions, as well as work accelerations required to overcome delays and suspensions, are the primary contributors to the cost overruns that affect many projects (Smith et al. [...]

In the quest to shorten project delivery time, construction professionals have the option of overlapping design and construction activities. Although time savings can be achieved by overlapping, conducting design and construction operations in a nonnatural sequence can carry significant risks. To mitigate these risks and make more appropriate overlapping decisions, concurrent engineering concepts can be used to classify upstream design activities in terms of design evolution and downstream construction activities in terms of sensitivity to upstream design changes. The focus of this work is to determine the factors that contribute to the sensitivity of construction activities. A series of semistructured interviews with experienced construction professionals show that the level of transformation, lead time, modularity, and the interaction of built components are some of the factors that determine the amount of sensitivity in construction activities to upstream design changes. These determinants provide for a quick assessment of an activity's sensitivity, which can help practitioners limit risk when planning the overlapping of design and construction activities. DOI: 10.1061/(ASCE)0733-9364(2009)135:3(199) CE Database subject headings: Construction management; Fast track construction; Planning; Design/build; Uncertainty principles.

This paper describes initial research on a project designed to understand the experiences of past generations of constructors and make that knowledge accessible to future generations of engineering students and construction practitioners. Much in the same way as medical students can trace their lineage back to Hippocrates, this project aims to provide architecture, engineering, and construction students, and professionals alike, a sense of their professional history. The project was developed around five time epochs, four geographic regions, and three different project types. We investigated issues such as the flow of money, training of workers, sharing of design knowledge, and nature of contracts and agreements. The central question posed by this work is how should knowledge of the history and evolution of construction practices be incorporated in the dialog that educators have with students and with the larger professional community? This research has led to multifaceted results. On the one hand, the message to students should be pride in their professional heritage because throughout time constructors and designers have used knowledge, perseverance, and innovation to accomplish remarkable projects. On the other hand, we have shown that much of what is considered new in the industry (alternative project delivery methods, worker safety programs, public private partnerships, and globalization) have historical antecedents and are not new at all. CE Database subject headings: Construction management; Delivery; Innovation; History.

A common method used to reduce project delivery time is to overlap sequential activities. Evolution and sensitivity characterizations of design activities provide a practical tool for identifying overlapping opportunities. The faster the evolution of information in an activity, the less risky it is to begin a downstream activity before the upstream activity is finalized. Also, the lower the sensitivity to changes in upstream information, the less risky it is to overlap activities. A methodology for determining the evolution and sensitivity of design activities has been developed through a series of expert interviews. The evolution of an activity can be determined by evaluating the levels of design optimization, constraint satisfaction, external information exchange, and standardization. The sensitivity of an activity can be determined by evaluating activity constraints, input variables, and the level of design integration. This framework for characterizing design activities in terms of evolution and sensitivity will lead to significant reductions in project delivery times. CE Database subject headings: Project management; Fast track construction; Construction industry; Building design; Delivery.

International construction involves all of the uncertainties common to domestic construction projects as well as risks specific to international transactions. Consequently, despite the worldwide trend toward globalization, a very small portion of contractors actively seek international contracts due to concerns of probable failures. This paper describes findings from experiments done to investigate the risk attitude and bid decision behavior in the selection of international projects. The participants demonstrated either weak risk seeking in profit situations or strong risk seeking toward loss situations when choosing between conflicting options of risky opportunities and sure payoffs. On the other hand, another experimental test attempting to investigate bid behavior when making a realistic bid or no-bid decision in a complicated international construction project reveals the prevailing risk aversion. Further, this paper finds the experimental supports for some of the errors and biases due to risk attitude that commonly exist in bid decisions in this area. Finally, we present lessons learned and guidelines to make a qualified bid decision through feedback with the participants. CE Database subject headings: Foreign projects; Project evaluation; Decision making; Risk management; Contractors; International factors.

The history of construction engineering and management education closely follows the emergence of the construction industry as an economic force in the United States. The initial introduction of programs in the post-World War II era was followed by specialization and the introduction of graduate construction specialties in the early 1960s. However, the lack of qualified individuals was recognized as a factor in successfully developing the construction engineering management (CEM) focus as an academic discipline. Today, that concern continues as CEM programs in the United States find themselves under attack by academic colleagues for issues such as lack of qualified faculty candidates and lack of funding opportunities. This paper addresses the status of the construction academic community by examining the common history of the CEM faculty through a genealogical approach, the historical research record through an examination of the publication record, and the questions that face a community that has appeared to slip from its intellectual peak. CE Database subject headings: Construction industry; Engineering education; History; Research needs.

While opportunities for international construction firms have been growing with globalization, the risks involved with international construction projects are increasing significantly. However, due to the complex skein of various risks, it is difficult to evaluate the severity of risk variables at the corporate level and to examine key success factors in an attempt to maximize a firm's value under the challenging global business environment. This paper focuses on a financial portfolio risk management for international projects to integrate the risk hierarchy of both individual projects and at the corporate level, which applies a multicriteria decision making method to maximize the total value of firms. To demonstrate the approach, a case study is conducted based on real projects collected from a multinational general contractor. Finally, we present lessons learned as well as guidelines for the application of these lessons to future projects through a workshop with industry practitioners. CE Database subject headings: International development; Corporate planning; Risk management; Financial management; Bids; Construction industry.

The uncertain physical and regulatory conditions prevalent in the field of environmental restoration often lead to considerable project cost growth. To date, the ability of project personnel to predict the magnitude of such growth has been limited. A formal approach to identifying, classifying, and incorporating uncertainty into standard cost estimating procedures is needed to quantify the risk of large-scale cost growth prior to project commencement. Because the elicitation of expert knowledge is critical to the risk analysis process, this paper evaluates the effectiveness of several approaches to eliciting and encoding probabilistic judgments. In essence we ask, 'How should one frame questions concerning uncertain judgments in order to get the best answers?' In addition, this paper examines using both influence diagramming and Monte Carlo simulation to model the uncertainties associated with environmental restoration projects.

A battery of expert system applications that support construction contract claims analysis is being developed in a research program at the University of Colorado in conjunction with the U.S. Army Construction Engineering Research Labs and U.S. Environmental Protection Agency. The collective name given to these systems is the Claims Guidance System. This paper describes a component piece of the Claims Guidance System called the Site Event Advisor (SEA). SEA was developed to help determine which of several claim types could flow from some unusual event occurring at a construction site. The system analyzes the characteristics of the event and the nature of the potential dispute, and suggests the kinds of claims (entitlement issues) that might likely arise from these circumstances. The system uses a production-rule-based inferencing system, and it acts as a front end to the other export system modules of the Claims Guidance System.

: Disputes and claims occur frequently in the construction process. The resulting litigation wastefully consumes important resources like time money, and especially project-engineering talent. Many contract disputes could be avoided if the disputing parties took fast action and were better informed. This paper reports on an ongoing research project to develop an expert system to educate and advise inexperienced site engineers about the legal consequences of construction disputes. The part of the system described in this paper is called SuperChange. It evaluates the validity of claims brought under the Changes clause found in the Federal Acquisition Regulations (FAR). SuperChange supports decisions made by site engineers in several important ways. First, SuperChange guides the user through the analysis by controlling the direction of the analysis based on previous user responses. By doing so, the system does not allow the site engineer to forget a crucial part of the analysis and at the same time trains the site engineer in the proper components of an analysis. The second way in which SuperChange supports the site engineer is by providing a comprehensive, hyper-text based, context-sensitive help system. The help system can provide explanation, court citations, examples, and quotations all related to the particular question at hand. The final way the system supports analysis is by providing a report-writing capability that can be used by the site engineer's superiors to review judgments and conclusions., Site engineers sometimes have to make legal judgments that can lead to costly claims and litigation. While low-cost legal advice may help reduce such risk, the real world does not afford this recourse. A progress report is presented on the development of an expert system program to aid and train tyro field engineers in evaluating legal consequences arising from contract disputes. The logic of SuperChange, which is patterned after Federal Acquisition Regulations language,makes it compatible with government construction projects. It is claimed that the system can help improve decisions of field engineers.

The world economy is becoming more global due to agreements such as the 'Uruguay Round' in the General Agreement on Tariffs and Trade. The globalization of the construction industry provides tremendous opportunities for contractors to expand into new foreign markets. However, international construction involves all of the uncertainties common to domestic construction projects as well as risks specific to international transactions. Consequently, in opposition to the worldwide globalization trend, only 19% of the U.S. top 400 contractors actively seek international contracts. This paper discusses current approaches related to entry decisions into international construction markets. It then develops a comprehensive approach for making stable and systematic go/no-go decisions for international projects. Finally, a pilot study is used to demonstrate and validate the approach.