Evaluation of elastic T-stress by the stress difference method
Evaluation of elastic T-stress by the stress difference method
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DOI：
10.1016/s0013-7944(99)00082-x
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发表时间：
1999-11
影响因子：
5.4
通讯作者：
Bo-Syung Yang;K. Ravi-Chandar
中科院分区：
文献类型：
--
作者：
Bo-Syung Yang;K. Ravi-Chandar
本文提出了一种计算裂纹尖端弹性T应力的简单方法--应力差分法，该方法结合了迭代单域双边界元法和在裂纹尖端施加零位移跳变的尖端节点法则。与I-积分法相比，该方法利用裂纹尖端前一点的σ 11与σ 22之差，能有效而准确地计算弹性T应力。通过对网格和裂纹尖端附近σ11−σ 22的空间分布的分析，验证了该方法计算T应力的收敛性。当应用于热弹性裂纹时，本文的应力差分法与相应的I-积分法也表现出很好的一致性。另一方面，本文提出的T应力检验方法由于其表达式简单，计算量小，明显优于I积分法。它还表明，尖端节点规则的裂纹尖端单元与定期多项式插值和节点分布提供了很好的估计的应力强度因子，在对比四分之一点的元素方法。
A simple method, called the stress difference method, is proposed to compute the elastic T-stress at a crack tip, incorporating the iterative single-domain dual-boundary-element method and a tip-node rule imposing zero displacement jump at the crack tip. In this method, the difference between σ11and σ22at a point ahead of the crack tip is demonstrated to be able to evaluate the elastic T-stress efficiently and accurately, in comparison to the I-integral method. Convergence of the T-stress computed by this method with mesh and spatial distribution of σ11−σ22near a crack tip was examined to validate the numerical technique for the T-stress. When applying to a thermoelastic crack, the present stress difference method also shows good agreement with the corresponding I-integral method. On the other hand, the present inspection method for the T-stress is obviously more advantageous than the I-integral method because of its simplicity in expression and much less computational effort. It is also shown that the tip-node rule for the crack tip element with regular polynomial interpolation and node distribution offers good estimates of the stress intensity factor, in contrast to the quarter-point element method.