基于加速加载的在役沥青混合料损伤与疲劳性能

Damage and failure performance of in-service asphalt mixture based on accelerated loading test

采用足尺加速加载试验模拟了现场沥青路面的在役状态,基于便携式地质地震波模量分析仪和劈裂试验对在役沥青混合料的损伤与疲劳性能进行了研究。结果表明:路面地震波模量随加速加载作用次数的增加而不断降低。基于地震波模量检测结果的频散曲线,分析了路面不同深度处地震波模量的衰变规律,发现下面层沥青混合料的临界损伤位置出现在其上部区域。在役沥青混合料的劈裂强度随加载作用次数的增加总体上略有降低。而加速加载作用对在役沥青混合料疲劳抗力的影响随着路面深度的增加而降低。

Accelerated loading test was carried out on an in-service asphalt pavement to study the damage and failure performance of in-service asphalt mixture using Portable Seismic Property Analyzer(PSPA)and indirect tensile test.The PSPA moduli of in-service asphalt mixture decreases with the increase in the accelerated loading passes.Based on the dispersion curves of PSPA test results,the relationship between the PSPA moduli at different pavement depth and accelerated loading passes was analyzed.It was found that the critical damage position of the bottom course of the asphalt layer appeared at the top area.According to the lab test results,the indirect tensile strength of the inservice asphalt mixture slightly decreases with the increase in the accelerated loading passes.With the increase in pavement depth the influence of the accelerated loading passes on fatigue resistance of the in-service asphalt mixture becomes weak.