G. Edward Gibson

Empirical Comparison of Design/Build and Design/Bid/Build Project Delivery Methods

This study compares the performance of design/bid/build and design/build to see if one project delivery method is superior in regards to time and cost. Similar military buildings were used to identify two samples of projects delivered with each of the two delivery methods. These projects provide a meaningful comparison because they include buildings of the same typology (i.e., U.S. Navy Bachelor Enlisted Quarters) delivered using similar design models. Project duration, project duration per bed, project time growth, cost growth and cost per bed were statistically compared. Upon completion of the analysis, the hypothesis that design/build projects are superior to design/bid/build projects in regards to time and cost was tested. Design/build projects were proven superior in performance in almost every measure. Other findings, including recommendations to practitioners and researchers, will be provided as well.

Performance Comparison of Large Design-Build and Design-Bid-Build Highway Projects

This study compares and analyzes the relationship of design-build (DB) and design-bid-build (DBB) project delivery methods with performance metrics of large highway projects (>

Changing Project Delivery Strategy: An Implementation Framework

50 million). Project performance is measured in cost, schedule, and change orders on these two types of highway projects. This study also investigates associations between project characteristics (input variables) and project performance (output variables) of large highway projects. The performance comparison methodology used here is derived from work done on a Texas Department of Transportation study of the State Highway 130 Project. The study results show that the construction speed and project delivery speed per lane mile (or lane kilometer) of DB projects were significantly faster than that of DBB projects for this sample. The study also showed that out of 21 inputs analyzed, 14 inputs have statistically significant associations with one or more outputs of these projects.

Benchmarking of Large Design-Build Highway Projects: One-to-One Comparison and Comparison with Design-Bid-Build Projects

For organizations such as departments of transportation, other public agencies, and private companies, adopting a new approach to procure services for delivery of construction projects requires significant organizational changes; modifications to both their work processes and existing organizational structures may be needed. Building on findings from a study of public owner organizations that have implemented the design-build method for delivering highway projects, the have developed a conceptual framework for helping owner organizations implement a change in their project delivery strategy. They further refined this framework by comparatively studying four transportation projects in the United States. In addition, many experts in the implementation of the design-build method for transportation projects participated in a Delphi study to validate the developed framework. In this article, the authors present findings from these studies, including application to the construction industry and to other industries.

Interactive simulation modeling for heavy construction operations

For generations, highway projects in the United States have been delivered with the traditional design–bid–build (DBB) project delivery method. In 1990, FHWA introduced Special Experimental Project Number 14 (SEP-14) to encourage state agencies to use more efficient alternative methods for delivering projects. As of 2002, approximately 140 SEP-14 projects have been built according to the design–build (DB) delivery method. Although the use of the DB method for transportation projects has increased noticeably in the past decade, attempts to measure project performance under DB as against DBB have been limited to small projects. To fill this research gap, an input-versus-output benchmarking approach was used to assess the performance of large DB highway projects. By means of this approach, factors that could affect performance of highway projects were identified, and a comprehensive methodology for benchmarking was developed. A sample of four DB projects (with contract amounts ranging from

Identification of Effective Management Practices and Technologies for Lessons Learned Programs in the Construction Industry

126 million to

Development of a project definition rating index (PDRI) for general building projects

1.4 billion) was analyzed to determine how project characteristics and DB practices (inputs) affect project performance in terms of cost and schedule (outputs). Project cost and schedule performance show clear trends against 15 input factors. More data points are needed to determine correlations between these inputs and outputs. In addition, 11 DBB projects (with contract amounts ranging from

Front End Planning for Infrastructure Projects

50 million to

PRE-PROJECT PLANNING AND ITS PRACTICE IN INDUSTRY

100 million) were selected for a statistical comparison with DB projects.

Front End Planning for Buildings

Abstract With all the benefits of discrete event simulation, the field application of simulation has been limited in the construction industry. The principal reasons for the limited field application include the complexity of simulation system itself and the amount of time and cost to develop the simulation model. To support the utilization of discrete-event simulation in the planning and the analysis of heavy construction operations, this paper proposes an interactive simulation modeling approach that will allow, with step-by-step guidance, the project manager to build a simulation model through interaction with a computer. To evaluate this modeling concept, this paper presents a framework for an information system that is called Knowledge-embedded, MOdularized Simulation system (KMOS), and then applies to a real project.