共线裂纹弹塑性双参数断裂分析  

ELASTIC-PLASTIC FRACTURE ANALYSIS OF DOUBLE CO-LINEAR CRACKS WITH J—A_2 method

作　　者：吴春笃[1] 王钟羡[2] 焦广臣[2] 

机构地区：[1]扬州环境资源职业技术学院环境科学与工程系,扬州225127 [2]江苏大学理学院,镇江212013

出　　处：《机械强度》2011年第4期597-600,共4页Journal of Mechanical Strength

摘　　要：用弹塑性双参数断裂理论分析共线双裂纹之间的干涉效应。计算不同裂纹尺寸与不同裂纹间距情况下主裂纹断裂驱动力J积分和约束参数A2。结果表明,随着载荷的增加,次裂纹对主裂纹的弹塑性干涉效应明显大于线弹性干涉效应,并且干涉效应随着裂纹间距的减小或次裂纹长度的增加而相应增大。当载荷比较大时,次裂纹的存在对主裂纹尖端的约束水平也有影响,裂纹尖端约束水平随着裂纹间距的减小或次裂纹长度的增加而相应增大。在采用工程简化方法对多裂纹问题进行断裂评定时,应该考虑次裂纹对主裂纹J积分和约束水平的影响。The interaction effect between double co-linear cracks is studied by using J—A2 elastic-plastic fracture theory.By using finite element analysis,the fracture driving force J-integral and constraint parameter A2 of the main crack are calculated with different crack sizes and the different distance of cracks.It shows that the interaction effect between co-linear cracks in elastic-plastic material is significantly bigger than that in elastic material when the load increasing to a particular level.The interaction effect increases with the increasing length of the adjacent crack or with the decreasing distance between the cracks.And,the constraint level of crack-tip is also influenced by the adjacent crack under large loading conditions.The constraint level of the crack-tip increases and the plastic zone reduces with the increasing length of the adjacent crack or with narrowing between the cracks.These negative factors should be taken into account in an engineering method to assess multiple cracks failure.

关 键 词：共线裂纹 干涉效应 断裂 有限元 弹塑性 

分 类 号：O346.1[理学—固体力学]