一种随机裂纹结构的裂纹扩展路径分析方法  

A CRACK PROPAGATION PATH ANALYSIS METHOD OF RANDOM CRACKED STRUCTURE

作　　者：姜潮[1] 龙湘云[1] 韩旭[1] 刘杰[1] 

机构地区：[1]湖南大学机械与运载工程学院,汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《固体力学学报》2014年第1期30-38,共9页Chinese Journal of Solid Mechanics

基　　金：国家自然科学优秀青年基金(51222502);教育部新世纪优秀人才支持项目(NCET-11-0124);全国优博专项资金(201235);装备预先研究项目(62501036012)资助

摘　　要：裂纹结构中存在大量不确定性因素,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.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.

关 键 词：随机裂纹结构 裂纹扩展路径 比例边界有限元 统计分析 

分 类 号：O346.1[理学—固体力学]