超薄磨耗层SAC-5沥青混合料设计及性能研究

为提供一种路用性能优良的沥青混合料作为超薄磨耗层用于预防养护工程,采用多碎石沥青混合料(SAC)级配设计方法设计了SAC-5沥青混合料。通过室内试验,对比分析了4%、6%、8%三种空隙率下混合料的路用性能。结果表明：SAC-5沥青混合料中粗集料含量占比达70%以上,当目标空隙率由4%增大8%时,混合料中矿料级配变化不大,最佳油石比减小；随着空隙率的增加,SAC-5沥青混合料的动稳定度、残留稳定度、残留强度比、构造深度及摆值均增加,低温弯曲应变减小,但仍满足规范要求；对于急弯陡坡等对抗滑性能要求较高路段,推荐使用目标空隙率8%的沥青混合料作为超薄磨耗层。

Research on Design and Performance of Ultra-thin Wear Layer SAC-5 Asphalt Mixture

In order to provide an asphalt mixture with excellent road performance as an ultra-thin wear layer for preventive maintenance engineering, the SAC-5 asphalt mixture was designed using the gravel asphalt mixture (SAC) grading design method. The road performance of the mixture under three porosities of 4%, 6%, and 8% was compared and analyzed. The results show that the coarse aggregate content in the SAC-5 asphalt mixture accounts for more than 70%. When the target porosity increases from 4% to 8%, the mineral aggregate gradation in the mixture does not change much, and the optimal oil-stone ratio decreases. With the increase of void ratio, the dynamic stability, residual stability, residual strength ratio, structural depth and swing value of SAC-5 asphalt mixture increase, and the low-temperature bending strain decreases, but still meets the specification requirements; For sections with steep slopes and other roads that require high anti-skid performance, it is recommended to use asphalt mixture with a target porosity of 8% as the ultra-thin wear layer.