摘要
基于分析势函数的二次变分，从理论上证明了固体材料不稳定性主要取决于材质不断退化的重要特征．另一特征是，材料往往会由基本变形路径漂移为一个轴向应变被限定的模态以至失稳．文中以有限元方法计算模拟受周期性分布孔洞损伤的平面板材模型，结果显示，孔周边的应变局部化使变形路径转移到一个轴向应变被限定的失效模态．此类现象与金属板材拉胀实验中所观测到的结果相符合．
Based on analyzing the second variation of potential functional, one of the char-acteristics of the instability occurred in solid materials is proved as basically depending on the deterioration of material behavior. Another important feature is demonstrated that the funda-mental straining path is used to be disturbed and shifted into a mode of limiting an axial strain at instability. Sheet materials perforated periodically are numerically analyzed by finite-element method to exemplify how the strain localization around small holes eventually turns the strain-ing path into a failure mode of strain limitation. Metal forming tests on steel sheets loaded by flat-bottom punch also indicates such shift of straining path when approaching to failure.
出处
《力学学报》
EI
CSCD
北大核心
2001年第3期332-339,共8页
Chinese Journal of Theoretical and Applied Mechanics
基金
国家自然科学基金(19872064)
非线性力学国家重点实验室资助项目.
