Abstract:
Overlay tester (OT) tests were carried out with different gradations, sample heights and air void to quantitatively evaluate anti-reflection crack performance of large stone porous asphalt mixes (LSPM) in this paper. Maximum load loss rate, first cycle load loss rate and loading cycle of 50% load loss rate were adopted for analysis, and anti-reflection crack prediction models based on sample height and air void were put forward. Finite element analysis of cohesion zone model in OT test was carried out to study the mechanism of different factors affecting anti-reflection crack. Results show that the load loss rate can be estimated by the natural logarithm model. The anti-reflection crack performance of LSPM-30 with different gradations can be more effectively evaluated with first cycle load loss rate and loading cycles of 50% load loss rate. The air void of samples has a more significant influence on the anti-reflection crack of LSPM-30 than that of the height, and the height of the anti-reflection crack samples in OT test is recommended to be no less than 70 mm in this study. The results of numerical analysis show that the crack type is I crack induced by the higher tensile stress/strain at the crack tip, which is mainly distributed in the interior of asphalt mortar and the interface between asphalt mortar and aggregate.