摘要
在文献[1]的基础上,本文分别对试件纤维区和剪切唇的应力结构进行考察.纤维区的应力结构特点为:可以进行变量z分离;对称面上的应力结构可由平面应变FEM解或HRR场解经应力三维度修正获得;载荷水平及试样厚度对应力结构的影响,可由厚度方向的CTOD得到反映,所得到应力表达式大为简便与直观.对剪切唇的应力结构进行考察,发现满足一定的精度可由插值法近似获得.本文提出了一种平面应变近似程度系数,并对此进行分析,该系数可较好地反映试样厚度、型式及载荷水平.本文也对断裂参量进行了分析,指出可对CTOD进行应力三维度修正获得.
Based on [ 1 ], the stress structures of the smooth region and shear lip of the specimens have been investigated in the paper. The characteristics of the stress structure in the smooth region have been found that: the variable z can be separated out. the stresses in the midsection can be obtained by the plane strain FEM results or HRR structure modified by the stress triaxiality. The effects of load level Hind thickness on the stress structure can be reflected by the distribution of CTOD along the thickness direction. The obtained expressions of the stresses are very simple and visualized. The analyses of the stress structure in the shear lip show that the stresses can be obtained by different methods of interpolation to a certain precise degree.
A new degree parameter of the plane strain state has been put forward and studied. The parameter can reflect relatively well the variation of the kind and thickness of the specimen as well as the load level. The fracture parameter has also been investigated to make sure that it can be obtained by modified CTOD with the stress triaxiality.
出处
《应用数学和力学》
CSCD
北大核心
1993年第9期775-785,共11页
Applied Mathematics and Mechanics
关键词
应力结构
裂纹尖端
试件
断裂力学
stress structure, singularity, Z1 region, stress triaxiality R, CTOD, shear lip interpolative m ethod, degree parameter of the plane strain state
