随机位移法在刚架稳定计算中的应用

The Application of Random Displacement Method in the Static Buckling of Frame Structure

将一种新的力学分析方法——随机位移法应用到刚架稳定问题的求解 ,以拓展其应用范围 .先将结构离散为一个有限自由度系统 ;然后根据有限自由度系统平衡稳定性的能量准则和随机位移法的基本原理 ,建立符合能量准则的载荷函数 ,该函数不为零的最小值即为临界载荷 ,由此将稳定问题转化为无约束的多维优化问题 ;最后应用遗传算法求出相应于最优解的目标函数值 .以实际算例为基础 。

A new mechanical method, random displacement method, was used to analyse static buckling of frame structure. The basic idea was to discrete the structure and find the load function according to the energy criterion of buckling and the principle of random displacement method. As the critical load is the minimum of the load function, a problem of frame buckling can be transformed into an optimization problem. Therefore, the critical load can be found through solving the optimization problem. The feasibility of the method is discussed on the basis of numerical computing instances.