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为研究动态荷载作用下沥青路面的力学特性及其使用性能,以Abaqus有限元软件为平台,建立沥青路面三维有限元动力分析模型,对比分析3种典型沥青路面结构的动力行为特征,进行路面性能评价,并开展沥青路面的结构组合优化分析。研究结果表明:随基层厚度增加,各动力响应量表现为路表弯沉、底基层层底应力和路基顶压应变逐步递减;面层层底应变和层间剪应力逐渐减小,并且随厚度增加,其变化逐渐减弱;当基层厚度<20cm,底基层承担较大弯拉应力,随基层厚度增大,基层逐渐成为主要承重层;半刚性路面(S1)整体刚度大,并能较好地抑制沥青层开裂及路基永久变形,倒装式路面(S2)的各项动力力学指标均处于不利状态,组合式路面(S3)的沥青层剪应力指标最优;采用动力指标与结构参数之间的正、负相关性及其显著性分析方法可更直观判别路面结构优化方向,为改善路面受力状态,对S1结构应提高基层厚度、降低面层模量,对S2结构应提高基层厚度,对S3结构应提高基层厚度与面层模量。
In order to study the mechanical properties and serviceability of asphalt pavement under dynamic loading, a three-dimensional finite element dynamic analysis model of asphalt pavement was established based on Abaqus finite element software. The dynamic behavior of three typical asphalt pavement structures was compared and analyzed. Evaluation, and to carry out the structural optimization of asphalt pavement analysis. The results show that with the increase of the thickness of the basement, the dynamic response is manifested as deflection of the road surface, the bottom stress of the basement and the top pressure of the subgrade gradually decrease; the strain and interlaminar shear stress of the surface layer decrease gradually, When the thickness of the base layer is less than 20cm, the basement layer undertakes greater bending and bending stress. With the increase of the basement thickness, the basement gradually becomes the main bearing layer. The overall rigidity of the semi-rigid road surface (S1) is large and can be better Which can restrain the cracking of asphalt layer and the permanent deformation of roadbed. The dynamic mechanical indexes of the inverted road surface (S2) are all in an unfavorable state, and the asphalt layer shear stress index of the combined road surface (S3) is the best. Between the dynamic index and structural parameters Positive and negative correlation and its significance analysis method can more intuitively determine the optimal direction of pavement structure. In order to improve the pavement condition, the thickness of the basement should be increased and the surface modulus should be increased for the S1 structure. The thickness of the basement should be increased for the S2 structure, S3 structure should be to improve the grass-roots thickness and surface modulus.