磁电热弹耦合材料三维多裂纹超奇异积分法

用超奇异积分方程法将多场耦合载荷作用下磁电热弹耦合材料内含任意形状 和位置三维多裂纹问题转化为求解一以广义位移间断为未知函数的超奇异积分方程组问题， 退化得到内含任意形状平行三维多裂纹问题的超奇异积分方程组；推导出平行三维多裂纹问 题的裂纹前沿广义奇异应力场解析表达式、定义了广义(应力、应变能)强度因子和广义能量 释放率；应用有限部积分概念及体积力法，为超奇异积分方程组建立了数值求解方法，编制 了FORTRAN程序，以平行双裂纹为例，通过典型算例，研究了广义(应力、应变能)强度因子 随裂纹位置、裂纹形状及材料参数变化规律，得到裂纹断裂评定准则. 最后，分析了裂纹间 干扰、屏蔽作用及其在工程实际中的应用.

MULTIPLE THREE-DIMENSIONAL CRACKS IN FULLY COUPLED ELECTROMAGNETOTHERMOELASTIC MULTIPHASE COMPOSITES

This work presents the hypersingular integral equation method to analyze the multiple three-dimensional cracks problem in fully coupled electromagnetothermoelastic multiphase composites under extended electro-magneto-thermo-elastic coupled loading through intricate theoretical analysis and numerical simulations. First, the problem is reduced to solving a set of hypersingular integral equations. Analytical solutions for the extended singular stresses, the extended stress intensity factors, the extended strain energy factors and the extended energy release rate near the crack front are obtained, respectively. The numerical method for the hypersingular integral equations subjected to extended coupled loads is proposed. Finally, numerical solutions of the extended stress intensity factors and the extended strain energy factors for two interacting three-dimensional cracks are given, and the effect of cracks orientation, interaction and shielding is discussed