超薄磨耗层与旧路面复合结构的高温稳定性研究

High Temperature Stability Analysis of Composite Structure Combining Ultra-thin Wearing Course with the Existing Pavement

试验研究结果表明:当旧路面中面层采用普通沥青时,复合芯样的变形量和变形率均明显大于中面层采用改性沥青时的情况。当中面层的沥青软化点较小、芯样复合蠕变速率较大时,其在高温条件下承载力不足,易发生塑性变形。此时由于变形不协调,超薄磨耗层出现了明显的结构性破损。沥青路面分车道养护加铺超薄磨耗层时,应重点关注旧路面的高温稳定性。

The experimental results show that when the middle layer is prepared with ordinar y asphalt in the existing pavement,the deformation value and deformation rate of composite core samples are obviously greater than the middle layer is prepared with modified asphalt.For the middle layer,when the softening point of asphalt is small and the composite creep rate of core sample is large,its bearing capacity is insufficient at high temperature,and plastic deformation is easy to occur.At this time,due to the uncoordinated deformation,the ultra-thin wearing course appears obvious structural damage.High temperature stability of the existing pavement should be paid more attention when ultra-thin wearing course is paved in lane-grade maintenance of asphalt pavement.