Methods of Reducing Joint Reflection Cracking: Field Performance Studies

Selecting rehabilitation options for Jointed Concrete Pavements (JCP's) continues to be one of the most challenging tasks for pavement engineers. In project 0-4517, the performance of numerous treatments was investigated. Reports 0-4517-1 and 0-4517-3 identified treatments that are performing well and those that are not. Report 0-4517-2 proposed a field investigation plan for testing future candidate projects that combines visual inspections with nondestructive testing (NDT). A sequenced approach is proposed for NDT evaluation that includes Ground Penetrating Radar (GPR) and deflection testing and in some instances Dynamic Cone Penetrometer (DCP) testing. Deflections can be taken with either the Falling Weight Defelctometer (FWD) or Rolling Dynamic Deflectometer (RDD). Three treatments were found to be performing well. For JCPs without major failures, the use of an asphalt overlay should be considered. Good agreement was found between field reflection cracking performance and the results from laboratory testing with TTI's overlay tester. Future overlay of JCPs should follow the overlay tester criteria proposed in this report. For sections with moderate levels of deterioration, with adequate support and no trapped moisture the use of rubblization is a good alternative. The rubblized concrete was found to provide a more uniform support than Crack and Seat. For those sections that are not candidates for rubblization because of poor slab support then a flexible base overlay appears to be a good alternative. The flexible base overlays on US 59 in Lufkin and US 83 in Childress are performing very well.