Evaluation of dowel bar retrofit for long-term pavement life in Washington State

The Washington State Department of Transportation (WSDOT) maintains approximately 2,400 lane miles of concrete pavements, many of which are on the heavily traveled interstate highway network. Many of these concrete pavements have more than doubled their intended performance life. Due primarily to traffic disruption, WSDOT has long recognized the potentially costly rehabilitation and reconstruction needs of the aging concrete pavement network. In 1993, WSDOT began dowel bar retrofitting its faulted concrete pavements. Dowel bar retrofit has had varied success in the United States, primarily due to construction techniques. In Washington State overall, dowel bar retrofit has been successful and has been determined to be a cost effective rehabilitation treatment. What is still unknown are the most applicable time or condition level (i.e. faulting and cracking condition) for applying dowel bar retrofit, its long‐term performance, and its failure mechanism. The outcomes of this study include guidelines for dowel bar retrofit project selection and construction best practices, a summary of dowel bar retrofit performance in Washington State, and estimated dowel bar retrofit project costs.