基于基本解的杂交有限元法计算应力强度因子
郑冠雨;王辉
【期刊名称】《郑州大学学报(工学版)》 【年(卷),期】2011(032)004
【摘要】Stress intensity factor is usually used to represent the stress singularity at tips of cracks embedded in engineering structures. With the displacement extrapolation method, the element-boundary integration-based hybrid finite element model is developed in the paper to determine the stress intensity factor for I-type cracks. In the hybrid formulation, the combination of fundamental solutions is used to approximate the element interior displacement and stress fields, while the conventional shape functions are employed to construct the element frame displacement fields. These two independent fields are linked by the hybrid functional and the element domain integral in the functional is converted to element boundary integral. Numerical examples show that the proposed hybrid method has good accuracy and can be used to analyze the crack problems.%含有裂纹的工程结构的应力奇异性表征通常需要借助应力强度因子.结合位移外推法,采用基于单元边界积分的杂交有限元法给出了平面Ⅰ型(张开型)裂纹的应力强度因子的计算方法.解析满足控制方程基本解的线性组合被用来近似表达单元内部的位移场和应力场,而普通的形函数插值则被用于近似表达单元边界位移场.二者通过杂交泛函联系起来,并且泛函中所有单元域积分被完全转化为单元边界积分.两个典型断裂问题