弹塑性离散结构的灵敏度分析

通过桁架实例说明了非线性结构响应对断面积的灵敏度，在材料刚度发生变化的点是不连续的；用传统的增量法不能准确地计算非线性响应灵敏度，用全局差分法计算非线性灵敏度也有特殊的困难。在分析其原因的基础上给出了非线性结构响应灵敏度值在间断点处跳跃值的算法公式，提出了增量法的修正公式。三杆桁架的例子被用来证明这些结论的正确性。

Computational aspects of sensitivity analysis of elastic-plastic discrete structures

The authors show that the sensitivity of nonlinear structural response is discontinuous at the transition point of the material stiffness. The traditional incremental procedure and its variants fai1 to predict the discontinuity of the structural response sensitivity. Unexpected difficulties may be encountered when the global finite difference scheme is used for nonlinear sensitivity analysis. This paper presents a formula for calculating the jump of the design sensitivity and an algorithm based on this formula as a remedy for the incremental scheme for nonlinear structural sensitivity analysis. Also the well-known three-bar truss example is investigated.