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 (>$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.