摘要
本文用边界元(BEM)和有限元(FEM)直接局部耦合技术把文献〔2〕中的奇异准协调元SQCE与BEM相耦合来计算应力强度因子。在裂纹尖端用很少几个奇异元,而在周围大部分区域用边界元,不仅克服了用BEM计算不对称重合裂纹时边界积分方程出现的不确定性,而且可充分利用单元SQCE和BEM的优点,达到降维、省时,提高精度和便于数据管理的目的。这对三维大型工程构件的断裂分析具有明显的意义。作为初步探讨,本文对各种二维断裂问题进行了计算,为向三维扩展打下了基础。
In this paper, the technique of direct local coupling BEM and FEM is used for the calculation of SIF. Only a few singular elements SQCE( 2 )are used at crack, tip, and boundary elements are used over large region at outside. In this way, not only the indeterminacy in the boundary integral equations for the calculation of non-symetric coincident cracks is overcome, but also the advantages of element SQCE and BEM can be fully utilized. It is achieved to reduce dimensions, save computer time, improve the precision of calculation and ease data preparation. All of these have explicit significance to the analysis of the 3-D large engineering structural components containing cracks. As initial study, the various 2 -D crack problems are computed in this paper, laid the foundation for the expansion to the 3-D problems.
