大跨空间结构的多目标等效静风荷载分析方法  

Multi-objective equivalent static wind loads for large-span structures

作　　者：陈波[1] 杨庆山[1] 武岳[2] 

机构地区：[1]北京交通大学,北京100044 [2]哈尔滨工业大学,哈尔滨150090

出　　处：《土木工程学报》2010年第3期62-67,共6页China Civil Engineering Journal

基　　金：国家自然科学基金(50808010);杰出青年基金(50725826);博士点基金新教师项目(200800041030);北京交通大学科技基金(2008RC015)

摘　　要：针对大跨空间结构风荷载空间分布复杂、多振型参与结构风振以及等效静风荷载中存在多等效目标等特点,以作者提出的单目标(即等效目标)等效静风荷载分析方法为基础,提出多目标等效静风荷载的分析方法,该方法的基本思想是:根据结构风振响应特性,选择风荷载的主要本征模态和结构主导振型惯性力作为构造多目标等效静风荷载的基本向量;根据最小二乘法,得到基本向量的最优组合系数,从而得到针对多个等效目标的等效静风荷载。该分析方法的优点是:能够再现风振响应特点,又能解决工程中的多等效目标问题。最后,将该方法应用于一单层球面网壳,结果表明:一个等效静风荷载分布形式就可以实现某一类响应(如所有节点的位移)都与动力极值响应等效,验证了本文方法的有效性和精度。Large-span space structures are characterized with complicated wind loads, multimode buffeting responses, and multiple equivalent objectives for equivalent static wind loads. A new method of analyzing equivalent static wind loads for multiple equivalent objectives is proposed, based on the method for single-objective equivalent static wind loads. According to the characteristics of wind-induced response, dominating eigen-modes of wind loads and dominating vibration modes are selected as the basic vectors to express equivalent static wind loads for multiple objectives, and a least square approximation method is employed for calculating the combination factors of these basic vectors. The equivalent static wind loads thus obtained may not only reflect the characteristics of wind-induced response, but also solve the key problem of multiple equivalent objectives. A single layer reticular shell is analyzed as an example. The results shows that the responses of all members under a single equivalent static wind distribution agree well with the peak values under the actual dynamic wind loads.

关 键 词：大跨空间结构 等效静风荷载 风振响应 本征模态 主导振型 

分 类 号：TU393.3[建筑科学—结构工程]