沿厚度非均匀复合材料的动态断裂力学研究

对于非均匀复合材料中多个裂纹的动态断裂力学问题，提出了一种分析方法，假设复合材料为正交各向异性并含有多个垂直于厚度方向的裂纹，材料参数沿厚度方向为变化的，沿该方向将复合划分为许多单层，假设单层材料参数为常数，Ｆｏｕｒｉｅｒ变换法，在Ｌａｐｌａｃｅ域内推导出了控制问题的奇异积分方程组并用虚位移原理求解，然后利用Ｌａｐｌａｃｅ数值反得刺裂纹尖端的动态应力强度因子和能量释放率，作为算例，研究了带有两个裂

DYNAMIC FRACTURE MECHANICS ANALYSIS FOR COMPOSITE MATERIALS WITH MATERIAL NONHOMOGENEITY ALONG THICKNESS DIRECTION

The problem considered here is the response of non homogeneous composite material containing some cracks subjected to dynamic loading. It is assumed that the composite material is orthotropic and all the material properties only depend on the coordinates y(along the thickness direction). In the analysis, the elastic region is divided into a number of plies of infinite length. The material properties are taken to be constants for each ply. By utilizing the Laplace transform and Fourier transform technique, the general solutions for plies are derived. The singular integral equations of the entire elastic region are obtained and solved by virtual displacement principle. Attention is focused on the time dependent full field solutions of stress intensity factor and strain energy release rate. As a numerical illustration, the dynamic stress intensity factor of a substrate/functionally graded film structure with two cracks under suddenly applied forces on cracks face are presented for various material non homogeneity parameters.