基层修补材料及荷载位置对沥青路面力学响应的影响

Influence of Base Repair Material and Load Position on Mechanical Response of Asphalt Pavement

摘要: 为了研究基层修补材料类型及荷载作用位置对沥青路面力学响应的影响，通过ABAQUS有限元软件建立三维路面结构模型，分析沥青面层、基层修补结构以及原基层等路面结构层相应的力学响应指标随修补材料弹性模量和荷载作用位置的变化规律。计算结果表明：修补材料与原结构的弹性模量越接近时，基层修补结构剪应力、原基层层底拉应力就越小，路面结构整体受力性能越好；修补材料的弹性模量为32,000 MPa时，基层层底拉应力最大值为0.21 MPa，是最小值的2倍。荷载作用于修补结构纵缝处时，沥青面层层底拉应变、基层修补结构层底拉应力等值均大于其他位置处的值；荷载作用于修补结构正中位置时，各结构层的应力应变均较小。基层结构疲劳寿命最大值出现在修补材料弹性模量与原材料最接近、荷载位于修补结构正中时，最大值为1.36 × 10¹⁰轴次，最小值出现在修补材料为柔性材料、荷载作用于修补结构纵缝处时，最小值为1.64 × 10⁹轴次，最大值是最小值的8.3倍。研究成果为选择基层修补材料类型及修补位置提供了参考依据。

Abstract: In order to study the influence of the type of base repair material and the location of load on the mechanical response of asphalt pavement, a three-dimensional pavement structure model was established by ABAQUS finite element software, and the change law of the corresponding mechanical response indexes of asphalt surface layer, base repair structure and original base with the elastic modulus of repair material and the location of load was analyzed. The results show that the closer the elastic modulus of the repair material to the original structure, the smaller the shear stress of the base repair structure and the tensile stress at the bottom of the original base layer are, and the better the overall mechanical performance of the pavement structure. When the elastic modulus of the repair material is 32,000 MPa, the maximum tensile stress at the bottom of the base course is 0.21 MPa, which is twice the minimum. When the load acts on the longitudinal joint of the repaired structure, the equivalent values of the tensile strain at the bottom of the asphalt layer and the tensile stress at the bottom of the repaired structure layer are greater than those at other positions; when the load acts on the middle position of the repaired structure, the stress and strain of each structural layer are small. The maximum fatigue life of the base structure appears when the elastic modulus of the repair material is closest to the raw material and the load is located in the middle of the repair structure; the maximum value is 1.36 × 10¹⁰ axial times. The minimum value appears when the repair material is flexible and the load acts on the longitudinal joints of the repair structure; the minimum value is 1.64 × 10⁹ axial times, and the maximum value is 8.3 times of the minimum value. The research results provide a reference for selecting the type and location of base repair materials.