Developing a Performance-Based Specification for Spray-Patch Crack Treatment – A Case Study in Alberta

摘要

A section of Highway (Hwy) 55 between Athabasca and Hwy 63 north of Edmonton, Alberta was planned to be spray-patched in early 2006 to treat dipped low temperature transverse cracks. This section comprised both a conventional granular base pavement structure and a full depth pavement structure most recently overlaid about 15 years earlier. Alberta Transportation (AT) has identified that the quality of workmanship can be a major installation issue with spray-patch treatments and can significantly affect the service life of the patch and the performance of the pavement. Therefore, it was considered to link the quality of the spray-patch treatment and resulting ride improvement, with payment to the maintenance contractor. The Hwy 55 project was selected to evaluate a performance-based specification, with price adjustments, based on the overall improvement in International Roughness Index (IRI). This paper provides background to the development of the performance specification, documentation of pavement treatment installation procedures, analysis of pre- and post-installation roadway profiles and IRI, and the resulting bonus payments. Performance of the spray-patch treatment and IRI after one year following installation is presented. Additionally, this project demonstrates the application of longitudinal profile data collected with a high-speed inertial profiler to evaluate changes in roadway profile and IRI due to the spray-patch treatment.