多轮荷载作用下的沥青道面结构响应敏感性分析

Sensitivity Analysis of Asphalt Pavement Structure Responses under Multi-wheel Loads

分析飞机多轮荷载作用下沥青道面表面弯沉、土基顶面竖向压应变、面层底面水平应力、基层或底基层底面水平应力对面层、基层或底基层厚度与模量、土基模量变化的敏感性。依托三维有限元平台对敏感性进行分析,选择B-777作为分析机型;以传统柔性类、沥青稳定类和半刚性道面作为分析结构。52种组合的分析结果表明:各力学响应量对土基都具有较高的敏感性,土基模量由30增至60 MPa的影响要大于60增至80 MPa;除传统柔性道面的面层底面水平应力外,底基层厚度对其他各响应量也具有较高的敏感性;层底的水平拉应力主要受上下层模量比影响,随着模量比的增加,上层底面开始出现拉应力,并逐渐增大,所以最大水平拉应力出现在传统柔性道面结构的面层底,沥青稳定基层的层底,以及半刚性基层的底基层底。

The response sensitivity of airport asphalt pavement structures based on 3D finite element analysis was presented.The deflection at the surface,the vertical compressive strain at the top of the subsoil,the horizontal stresses at the bottoms of the surface layer,base and subbase vary with the thicknesses and moduli of the pavement structure layers were discussed.B-777 was selected as the aircraft type for analysis,the asphalt pavement structures with conventional flexible base,asphalt stabilized base,and semi-rigid base were submitted for analysis.The results of 52 structural combinations show that（1） the mechanical responses of different pavement structures are sensitive to subsoil modulus,it is more sensitive for subsoil modulus changing from 30 to 60 MPa than from 60 to 80 MPa;（2） except horizontal stress at the bottom of the surface layer of conventional flexible pavement,the subbase thickness has high sensitivity to most responses;（3） the horizontal tensile stress at the bottom of the structure layer is influenced by the modulus ratio of above and beneath layers,the tensile stress appears and increases with the increase of modulus ratio,so the largest horizontal tensile stress appears at the bottom of the surface layer of conventional flexible pavement,at the bottom of the base of asphalt stabilized asphalt pavement,and at the bottom of subbase of semi-rigid asphalt pavement.