基层类型对沥青路面交叉口剪应力响应影响分析

Effects of Base Materials on Shear Stress of Asphalt Road Intersection

城市道路交叉口的基层类型复杂.为准确评估不同基层类型对交叉口沥青路面结构力学响应的影响,本文通过建立路面结构三维有限元分析模型,在考虑竖向和水平动态荷载共同作用的基础上,分析五种不同基层和面层类型路面结构组合的力学行为差异.结果表明:柔性基层路面结构内部的剪应力水平高于水泥混凝土路面加铺层和水泥混凝土桥面铺装层结构内部的剪应力水平;在双层沥青面层中,下面层内部的剪应力水平普遍低于上面层剪应力水平;水平力的作用将显著增加沥青面层内部水平剪应力,从而加剧沥青面层发生车辙、推移、拥包等病害的发生概率及发展速率.层间连续状况对横向和纵向剪应力的影响不大,但对水平剪应力的影响十分明显.

Base materials used in the asphalt road intersection are complicated.To precisely evaluate the effect of the base types on the dynamic response of the asphalt road intersection,a three-dimensional numerical modeling of five different pavement structures with different base and pavement materials were built by using finite element(FE)method.Both vertical and horizontal loads were considered during the FE simulation.The simulation results show that the shear stress of the pavement structure with flexible asphalt base is much lower than that with Portland Cement Concrete(PCC)base,which is rigid.The shear stress of the asphalt bottom layer is less than that of the surface layer for the double-layer pavement.The horizontal load significantly increases the horizontal shear stress within the asphalt pavement,which increases the risk of rutting,upheaval and traction of the asphalt layer.The interlayer bonding between the asphalt layer and the PCC base has negligible effect on both the transverse and longitude shear stress,but the bad interlayer bonding can considerably increase the horizontal shear stress within the asphalt layer.