变截面连续梁的初始后屈曲分析

The Initial Post-Buckling Behavior of Continuous Beams with Variable Cross Sections

基于Ｋｏｉｔｅｒ理论，提出了一个分析变截面连续梁初始后屈曲的方法。它的主要原理是借助传递矩阵的概念，首先导出连续梁在临界状态下首跨右端（或末跨左端）的刚度系数算式，然后进一步考虑后屈曲时该系数由于超临界变形所引起的变化，从而可将连续梁的初始后屈问题化为带弹性支承的单根粱处理。实例表明了这一方法的有效性．

An analytical method based on Koiter′s theory for thecalculation of the initial post-buckling behavior of continuous beams with variable cross sections is presented.An expres-sion for the stiffness coefficient of the right end of the first span in the continuous beam inthe critical state is derived with a transfer matrix. Then the variation of the coeffident due tofinite flexural deformation of the beam in the postbuckling state is taken into account , reducing the problem to one of a single beam with elastic supports. The feasibility of the approachis proved by examples.