中文摘要：

为了更好地预测沥青混合料的动态模量，利用工业CT采集数字图像，并与数值模拟技术相结合，从三维细观尺度研究了混合料结构对其性能的影响。首先采用工业CT扫描沥青混合料试件，获取其内部的真实三维细观结构，再开发程序建立沥青混合料的三维数值试样。将沥青混合料中的集料设为弹性体，将沥青砂胶设为粘弹性体，并采用修正的广义Maxwell模型表征，拟合出Prony级数的剪切松弛模量参数，作为有限元的输入参数。最后进行不同温度和频率下的沥青混合料间接拉伸动态模量数值模拟。结果表明：预测值和实测值吻合良好，基于三维细观尺度预测沥青混合料动态模量切实可行；该方法克服了传统沥青混合料数值模拟方法的局限性。

英文摘要：

In order to predict the dynamic modulus of asphalt mixture more accurately, with X-ray CT for the digital image processing and numerical simulation technique, the influence of asphalt mixture structure on its mechanical properties was studied from 3D microscopic scale. The asphalt mixture specimens were scanned to obtain the real internal 3D microstructure with X-ray CT. The program was developed to build up 3D digital specimen. Aggregates were assumed to be elastic and sand mastic was viscoelastic. They were characterized by modified Generalized Maxwell Model. The shear relaxation module parameters as finite element parameters were obtained through fitting Prony series. Finally, the numerical simulation of dynamic modulus based on indirect tensile test was conducted under different temperatures and loading frequencies. The results indicate that the predicted values agree well with the actually measured values. Predicting dynamic modulus of asphalt mixture incorporated with real 3D microstructure based on finite element method is a promising application to conduct research on asphalt concrete. This method overcomes the defects of conventional numerical simulation method of asphalt mixture.