Abstract
The performance of a construction project is attributed to several determinants, where the project risks play a substantial role. Selecting an appropriate delivery method is among one of many factors affecting project performance. There are a number of project delivery options ranging from the traditional design-bid-build to alternative delivery methods including design-build (D-B), construction manager/general contractor, and public-private partnerships. In particular, D-B has been increasingly used because of its documented benefits such as the potential of shortening project schedule, enhancing innovation, and reducing adversarial relationships among project players. However, D-B also gives room for increased risks for both the contractor and the owner if the risks are not managed efficiently. Previous studies have attempted to identify and analyze the risks on D-B projects but have not fully addressed the influence of risks on the cost growth of a project. Building upon the previous work, this study analyzes 118 D-B highway construction projects using structural equation modeling (SEM) to identify the pertinent relationship between risks and project cost growth. These project data were collected from completed highway projects between 2004 and 2015. The risks are categorized under five critical factors namely environmental and complexity risk, utility and right-of way (ROW) risk, construction method and contract risk, permit risk, and construction procurement/design risks using confirmatory factor analysis. The project cost growth is determined based on the project cost variation from the award to the final cost. Results from SEM indicated that utility and ROW risks, procurement and design related risks, environmental risks, and permit risks have a strong positive correlation with the cost growth of D-B projects.