基于断裂力学理论的结构裂纹扩展机理分析

Analysis of structural crack expanding mechanism based on fracture mechanics theory

阐述了断裂力学理论的研究现状及应用范围,同时基于断裂力学理论,对结构断裂的扩展机理进行分析,论述了3种不同裂纹类型的应力强度因子对裂纹扩展的影响。同时,利用有限元分析软件Abaqus设立位移增量分析步,对裂纹扩展全过程进行模拟,并运用断裂力学理论对结构断裂的扩展过程进行更详细分析。研究结果表明:结构中裂纹扩展与否,与裂纹的应力强度因子有着必然联系,当裂纹的应力强度因子大于其断裂韧性时,裂纹将发生扩展。

This article expounds the research status and application scope of fracture mechanics theory.Based on the theory of fracture mechanics,the expanding mechanism of structural fractures is analyzed,and the effects of stress intensity factors of three different crack types on crack expanding are described.At the same time,the finite element analysis software Abaqus is used to set up the displacement increment analysis step for simulation of the entire crack expanding process,and the fracture mechanics theory is used to analyze the structural fracture expanding process in more detail.The results show that the crack expanding of the structure is necessarily related to the stress intensity factor of the crack.When the stress intensity factor of the crack is greater than its fracture toughness,the crack will expand.