三维矩形板1/4椭圆角裂纹的通用权函数

对三维矩形板1/4椭圆角裂纹的通用权函数进行了研究.基于有限元方法计算了裂纹面承受沿宽度方向的均布、线性分布和2次分布应力时的参考应力强度因子解,建立了形式较为统一、较高精度以及适用范围相对更宽的参考应力强度因子近似表达式.在此基础上获得了三维矩形板1/4椭圆角裂纹的通用权函数,最后采用裂纹面分别承受3次、5次和7次幂函数分布应力下的应力强度因子有限元解对通用权函数的计算精度进行了检验和验证.结果表明:建立的通用权函数相比已有的通用权函数精度由4%(A点)和6%(B点)提高到1.06%(A点)和1.6%(B点),补充验证的7次幂函数分布载荷下的应力强度因子通用权函数解的精度达到3.67%(A点)7.45%(B点). 

General weight functions for corner quarter-elliptical crack in three-dimensional rectangular plate

General weight functions of the corner quarter-elliptical crack in three-dimensional rectangular plate were studied. Uniform, higher-precision and relatively wider-application-range approximate expressions of reference stress intensity factors were obtained, by using the reference finite element data of the stress intensity factor when the crack surface was subjected to in-plane uniform, linear and secondary power law distribution loading along the plate width. On this basis, the general weight functions of the corner quarter-elliptical crack in three-dimensional rectangular plate were obtained, the accuracy of the general weight functions was validated by finite element method finally when the crack surface was subjected to in-plane 3,5,7 times power law distribution loading. The results show that the accuracy of established general weight functions is raised from 4%(point A) and 6%(point B) to 1.06%(point A) and 1.6%(point B) compared with the existing general weight functions. The accuracy of complementary validation of stress intensity factors calculated by general weight function method under seven times power law distribution loading reaches 3.67%(point A) and 7.45%(point B).