钢结构的弹塑性大位移研究分析

为了探讨钢结构的高等分析和设计方法，本文作者应用泛函的最小势能原理，将经典的梁柱理论与非线性有限元法相结合，提出一种钢结构弹塑性大位移研究分析的简化单元模式和计算方法。它考虑了结构大位移、轴力的P-Delta效应、残余应力、轴力使杆件截面极限弯矩的变化、截面刚度退化和塑性区长度等非线性因素的综合影响。通过一个典型钢框架的非线性全过程分析，说明了该法的实际应用。算例表明，本文方法是可靠的，可供工程设计人员参考。

Advanced large-displacement elastic-plastic analysis for steel structures

For exploring the advanced analysis and design method of steel structures, presented in this paper are a simplified element model and a relevant calculating method for an advanced large- displacement elastic-plastic analysis of steel structures by applying the principle of functional minimum potential energy and by combining traditional beam-column theory with nonlinear finite element method. The present model and the method have taken into account the various nonlinear factors from the structural large-displacement, P-Delta effect of axial force, residual stress, changes in the plastlc-moment capacity at plastic hinges due to changes in axial force, degradation of cross-sectional tangent stiffness and plastic zone length, which affect the element stiffness matrix. The practical application of the present method is further stated by a nonlinear full-range analysis for typical steel framed example. Numerical results show that the present method is reliable and is helpful to engineers in structural design.