中文摘要：

裂纹结构中存在大量不元宝性因素，如裂纹长度、材料性质、外部载荷等，裂纹扩展路径的不确定性分析对研究随机裂纹结构损伤和断裂的力学特性并预测其性能及可靠性具有重要意义。论文提出了一种适应于混合载荷模式下随机裂纹结构的裂纹扩展路径分析方法，该方法考虑了裂纹长度、材料性质和外部载荷等的随机性，并通过蒙特卡洛方法对随机参数空间进行采样，采用比例边界有限元方法计算结构应力强度因子，进而模拟单次裂纹扩展路径，在此基础上，通过概率分析方法获得随机裂纹结构中裂纹扩展路径的统计特性，最后给出了两个数值算例验证了论文方法的有效性。

英文摘要：

There are many uncertainty factors such as crack length,material properties and external load,ere in eracked structures,and the crack propagation path uncertainty analysis is necessary for a better understanding of their mechanical properties including damage and fracture and also useful for predicting the performance and reliability. This paper proposes a crack propagation path analysis method in random cracked structures under mixed model loads. The method takes into consideration the randomness of crack length, material properties and external loads,ere and adopts the Monte Carlo method to sample from lhe random parameter space. The scaled boundary finite element method is adopted to calculate the stress in tensity factors and simulate the crack propagation path. On this basis,a statistical analysis method is pres enled to oblain the statistical properties of the crack propagation path in random cracked structures. Finally two numerical examples are presented for verification of the validity of the proposed method.