基于复合材料细观力学模型的沥青混凝土弹性模量预测

Elastic Modulus Prediction of Asphalt Concrete Based on Composite Material Micromechanics Model

针对目前预测沥青混凝土弹性模量的主要方法(基于宏观层面的试验法和经验法)均未能反映其细观结构的问题,基于复合材料细观力学方法建立了沥青混凝土多相的2层嵌入式细观力学模型,求解得到单夹杂复合材料的2个弹性常数(弹性模量和剪切模量);结合多步骤方法,即将各档粒径集料与空隙逐一投入,然后进行均匀化,得到多夹杂复合材料弹性模量,并与试验值进行对比。结果表明:预测结果与试验结果基本相同;该方法能够反映各组成材料在沥青混凝土中所起的力学作用;沥青混凝土的空隙率、沥青胶浆的弹性模量对沥青混凝土的弹性模量有重要影响。

Aimed at the problem that the main methods of predicting elastic modulus at present are experiment method and empirical method based on macro level and can not reflect the microstructure of asphalt concrete,based on composite material micromechanics method,a two-layer built-in micromechanics model was employed to obtain two elastic constants（elastic modulus and shearing modulus） of composite material with a single inclusion.Then,using the stepping method,namely every kind of inclusion was treated individually and the effective elastic modulus was calculated in each step.The elastic modulus of composite material with multi-inclusion was derived.It was compared with test value.Results show that predicted result agrees well with test result.This model can reflect the roles of constituent materials in composite material.Air void and elastic modulus of asphalt mixture have great influence on elastic modulus of asphalt concrete.