各向异性复合材料尖劈和接头的奇性应力指数研究

Stress Singularities in Tips of Three-Dimensional Anisotropic Multi-material Wedges and Junctions

提出了一个新的、基于位移的、求解三维尖劈端部奇性应力指数问题的非协调元特征分析法。该方法假定尖劈端部邻域内的位移场没有采用奇异变换技术 ,导出虚功方程的出发点不同于过去原有求解裂纹尖端近似场的有限元特征分析法 ,在有限元离散时采用的单元形式为非协调元。文中运用该方法给出了若干求解各向异性复合材料尖劈 接头端部奇性应力指数的算例。所有的计算结果表明 ,本文方法能够求解复杂尖劈 接头的全部奇性应力指数 ,使用的单元少而且精度高。

s: In this paper a new non-confirming finite element eigenanalysis method based on displacement is developed to solve the stress singularities surrounding a wedge tip. It is assumed that the singular transformation technique is not used in displacement fields assumption surrounding the wedge tip, the jump-off that educes the formula is different from existing finite element eigenanalysis methods for asymptotic fields near the crack tip, the virtual work equation is discretized by non-confirming elements. This paper presents some illustrative evaluating examples of three-dimensional anisotropic multi-material wedges and junctions, in which the stress singularities are solved. All calculations show that the present method can be used to calculate all the stress singularities of the complex wedges and junctions, needs fewer elements, and yields more accurate results than available methods do.