静载荷作用下三维线弹性弯曲裂纹路径预测  

Three-dimensional static linear elasticity crack path prediction

作　　者：陈冲[1,2] 杨大鹏 CHEN Chong;YANG Dapeng(Department of Urban Rail Transport,Zhengzhou Technical College,Zhengzhou 450121, China;School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;Postdoctoral Mobile Station of Mechanical Department, School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan 430074,China;Department of Material Engineering,Zhengzhou Technical College,Zhengzhou 450121, China;School of Naval Architecture & Ocean Engineering,Huazhong University of Science and Technology, Wuhan 430074,China)

机构地区：[1]郑州职业技术学院城市轨道交通系,河南郑州450121 [2]上海交通大学材料科学与工程学院,上海200240 [3]华中科技大学土木工程与力学学院力学系博士后流动站,湖北武汉430074 [4]郑州职业技术学院材料工程系,河南郑州450121 [5]华中科技大学船舶与海洋工程学院,湖北武汉430074

出　　处：《中国科学技术大学学报》2019年第9期723-730,共8页JUSTC

基　　金：2017 Science and Technology Research Plan Project of Science and Technology Department of Henan Province(172102210567).

摘　　要：利用二阶摄动方法研究了静载荷作用下结构线弹性裂纹的弯曲扩展问题、裂纹路径预测时的应力准则与能量准则之间的关系,并求解出三维静态应力强度因子.归纳总结出三维线弹性弯曲裂纹扩展的判据,求解出三维线弹性弯曲裂纹扩展过程中的形状参数.利用Irwin公式计算出三维弯曲裂纹扩展引起的静态能量释放速率.研究了具有非均匀断裂韧性的材料的三维静态弯曲裂纹.就均匀物质而言,在二阶摄动分析理论的框架内,两种准则指明了相同的三维静荷载弯曲裂纹扩展路径.但在具有非均匀断裂韧度的物质中,能量准则优越于应力准则.对三维静态弯曲裂纹路径失稳因素进行了比较和分析,研究了不同初始三维裂纹长度下材料退化与静施应力或外静应力之间的临界关系.Three-dimensional static stress intensity factors were analyzed for a curved crack by using a second order perturbation method.The method was extended to obtain an approximate representation of a three-dimensional static stress intensity factors at the tip of a curved crack.The criterion of elastic bending crack propagation the three-dimensional body was summarized.The shape parameters of three-dimensional linear elastic bending crack propagation were figured out.A static energy release rate due to three-dimensional curved crack growth could be calculated by using Irwin’s formula.Considerations were made for a three-dimensional static curved crack in materials with inhomogeneous fracture toughness.As far as homogeneous matter was concerned,in the framework of the second-order perturbation analysis theory,the two criteria indicated the same three-dimensional static load bending crack propagation path.However,the energy criterion was superior to the stress criterion in materials with non-uniform fracture toughness.Three-dimensional static curved crack path destabilizing factors were compared and analyzed.Critical relations between the material degradation and the static applied stress or the outer static stress for various initial three-dimensional crack lengths have been studied.

关 键 词：二阶摄动方法 三维静态应力强度因子 弯曲裂纹 断裂韧度 静施应力 

分 类 号：TP301[自动化与计算机技术—计算机系统结构]