结构在随机激励下的一种动力学设计方法

A DYNAMIC DESIGN METHOD FOR STRUCTURE UNDER RANDOM EXCITATION

提出一种将结构在随机激励下，某些给定点（自由度）上响应首次超过允许极限而发生破坏的条件作为约束的动力学设计方法。文中分析了广义随机激励不相关与相关两种情况，并推导了各自情况下任一给定点（自由度）上的期望穿阈数对于设计变量的灵敏度计算公式。所导公式适用于宽带平稳高斯随机激励。算例表明，所提方法是有效与可行的。

This paper presents a dynamic design method in which the failure condition of first passage of response for certain points (DOFS) on the structure to random excitation is regarded as a constraint. Two conditionsof correlated and uncorrelated generalized random excitation are analysed and accordingly,the sensitives of r:.,theexpected number of crossings of the level a during unit time with positive slope (i. e when the signal x. crosses thelevel a from below to above),with respect to the design variables are also deducted. The formulas are applicable tostationary Gaussian random excitation. Computational simulation shows the feasibility and efficient of the proposedmethod.