Performance Evaluation of Cold and Hot Asphalt Patching Materials with Effect of Preheating

Asphalt pavement pothole repair with either cold mix asphalt (CMA) or hot mix asphalt (HMA) has been one of the most important and frequent maintenance activities for highway agencies. This study evaluated the performance of different patching materials and the effect of preheating by conducting laboratory experiments. Indirect tensile strength (IDT) and interface shear strength tests were performed on various CMA and HMA with different RAP contents. The results show that the performance of commercial CMA largely depends on curing time. They exhibited higher strength than bulk cold mix after a certain curing period. For HMA, its IDT strength increased with RAP content while the interface shear strength was observed to be independent of RAP. With the application of preheating, interface shear strength of both CMA and HMA was enhanced. Compared with HMA, the IDT strength of CMA was much lower regardless of curing time, and the interface shear strength of CMA depends on both curing time and material type.