级配碎石厚度对倒装式沥青路面结构受力及寿命的影响研究

Research on Influences of Graded Macadam Thickness on Inverted Asphalt Pavement Structural Stressing and Life

文章以宿迁市326省道大修工程为依托,针对不同的级配碎石基层厚度,采用BISAR软件对沥青路面进行了力学计算,分析了路表弯沉、沥青面层底拉应力、半刚性基层底拉应力和沥青面层内竖向应力最大值产生的位置,以及随级配碎石层厚度的变化趋势,并对倒装式沥青路面寿命进行了研究。结果表明:随着级配碎石基层厚度的增加,路表弯沉呈线性减少趋势,半刚性基层底拉应力、不同层位的竖向应力和沥青路面的疲劳寿命逐渐减少,趋势逐渐变缓,沥青面层底拉应力逐渐增加,趋势逐渐变缓;级配碎石基层的设置及其厚度的增加对基层未开裂的沥青路面设计是不利的,但可减少基层开裂对沥青面层的影响。

Combining with provincial highway 326 overhaul project in Suqian, asphalt pavement stress with different grades macadam base thickness was calculated by software BISAR, surface deflection, bottom tensile stress of asphalt surface layer, semi-rigid bottom tensile stress and the location of maximum vertical stress of asphalt pavement inner surface, as well as thickness changing trend over graded gravel layer were analyzed, the inverted asphalt pavement life was also studied. The results showed that： with the increasing of graded gravel base thickness, road surface deflection linearly decreasing, semi-rigid bottom tensile stress, vertical stress of different layers and fatigue life of asphalt pavement are reduced, bottom tensile stress of asphalt surface layer is gradually increased; graded macadam setting and thickness increasing are unfavorable to asphalt pavement design without base crack, but it can reduce the influence of base cracking on asphalt surface.