考虑屋面板自振效应和流固耦合效应的大跨度空间结构风振系数

Wind vibration coefficient of long-span spatial structures with self-oscillating of roof and fluid-structure coupling effect

为了得到屋面板自振效应和流固耦合效应对大跨度空间结构风振系数的影响,首先对不同风速时程数值模拟方法的计算效率和计算精度进行比较,确定适合大跨度空间结构风速时程数值模拟的方法;分别针对考虑屋面板自振效应和流固耦合效应推导了风荷载计算公式;对天津奥林匹克中心体育场大跨度钢管桁架结构和某体育馆屋盖大跨度单层球面网壳结构进行风振系数计算分析。结果表明,考虑屋面板自振效应,结构风振系数增大;考虑流固耦合效应,结构风振系数减小,且风和结构的耦合起主要作用,风和屋面板耦合的影响很小,可忽略不计;同时考虑屋面板自振效应和流固耦合效应,结构风振系数分布规律基本不变,屋面板自振效应与流固耦合效应对结构风振系数的影响不能相互抵消,且对不同结构影响程度不同。

The influences to the wind vibration coefficients brought by self-oscillating effect of roof and fluid-structure coupling effect were studied in the paper. The efficiency and precision of different wind numerical simulation methods were compared and then the appropriate method for wind vibration analysis of long-span spatial structure was adopted. The calculating formulas were derived with self-oscillating effect of roof and fluid-structure coupling effect respectively. The wind vibration coefficients of the roof structure of the Tianjin Olympic Stadium and a single-layer reticular shell of a gymnasium, both of which are long-span spatial structures, were analyzed. The calculation results show that the wind vibration coefficients increase with self-oscillating effect of roof, while they decrease with fluid-structure coupling effect. The wind-structure coupling effect plays a main part, while the wind-roof coupling effect which could be neglected has little influence. The influences, which are brought by self-oscillating effect of roof and fluid-structure coupling effect respectively, can not be canceled out by each other, and the degree of influence varies with different structures.