摘要
提出一种在确定结构极限载荷时增量弹塑性有限元法中载荷增量步长的优化分析方法。当结构外载荷超过极限载荷时，增量法迭代求解过程中应力点不能回退到屈服面上，引起迭代发散。通过以每增量步中迭代收敛为目标函数，优化载荷增量步长，当步长被优化到无穷小时，迭代才收敛，则此时的外载荷为这种加载方式对应的极限载荷。实例表明可得到较高的计算精度。
This artical presents an analytic method to detemine load incremental factor by incremental elasto-plastic FEM as the load comes to limited one. When the actual load exceeds the limited load, the stress point is unable to move back to the yield field, which makes iteration diverge. Optimal load incremental factor can be computed by taking the iteration process converging as the objective function When the iteration process can not converge until the computed factor becomesinf initesimal, the load can be considered the limited load corresponding to this loading method. The examples show that the method has high calculating precision.〖KH*2D]
出处
《华北电力大学学报（自然科学版）》
CAS
北大核心
1997年第4期71-76,共6页
Journal of North China Electric Power University：Natural Science Edition
关键词
弹塑性有限元法
增量法
极限载荷
elasto-plastic FEM,incremental method, limited load
