沥青路面永久变形设计方程研究

Study on the Design Equation of Permanent Deformation of Asphalt Pavement

对于半刚性基层、刚性基层、柔性基层、组合式基层的沥青路面典型结构,计算出不同季节时不同深度处沥青混合料的温度和动模量,采用分层总和法计算出路面总永久变形,计算出平均塑性应变点的深度和弹性应变,并在路面总永久变形和季节平均气温、面层厚度、平均塑性应变点的弹性应变以及标准轴载累积作用次数间建立了回归公式,相关系数(R2)均在0.93以上,最后建立了沥青路面永久变形预估方法。结果表明,可以利用本文的方法来代替分层总和法预估沥青路面的永久变形,但前者更简单实用。

For the asphalt pavement with different base courses,the temperature and dynamic modulus of asphalt mixture in different season and different depth were calculated,the permanent deformation prediction model in AASHTO 2002 Highway Design Guide were used,the total permanent deformation of asphalt pavement were calculated with layers summation methods,and the depth,in which the plastic strain was equal to the average plastic strain,and the elastic strain at this depth were determined.The regression formula,between the total permanent deformation and the average air temperature in different seasons,surface course thickness,number of axle load and the elastic strain at the depth in which the plastic strain was equal to the average plastic strain,were established.The square of the correlative coefficients were greater than 0.95.At last,the prediction method for the permanent deformation of asphalt pavement was found.Results show that the layers summation method can be replaced by the method found in this paper to calculate the permanent deformation and the later is more simple and useful.