非共面半椭圆形表面裂纹群问题的现代分析法

A Modern Analysis Approach to Non—coplanar Semi—elliptical Surface Cracks

本文发展了体积力法的工作,建立了能有效地分析半无限体中交错型表面裂纹群相互干涉效应的改进型体积力法。在数值分析上,本文还作了以下两点修正:一、从直觉的物理概念出发,考虑了材料泊松比对应力强度因子的影响;二、从应力影响系数的物理意义出发,提出了能有效地处理复合型表面裂纹耦合积分奇异性问题的间接法。作为改进法的应用,本文给出了二个形状比相同的非共面半椭圆形表面裂纹相互干涉效应的计算结果。

This paper develops the body force method to a modified mathematical expressions which can analyze effectively the interference effects of staggered surface cracks in a semi—infinite solid.Two modifications are also made according to the fundamental principle. One is the consideration of the effect of Poisson ratio on the stress intensity factors from physically intuitional concept, and the other is the estabilishment of indirect method for dealing with the coupled integral singularity encountered in mixed mode problems by means of the physical meaning of stress influence coefficient.As an illustration of the application of the proP9red method, the computational results for the interference effects of two staggered semi—elliptical surface cracks with the same aspect ratio are presented.