屋盖悬挑端加固减振试验研究

Experimental research on reinforcement and vibration reduction of the cantilevered roof

大跨网架屋盖挑檐部分风致响应较大,提出附加杆件、粘弹性阻尼器及粘滞阻尼器三种加固减振方法。设计制作正置四角锥体单元空间网架足尺子结构试验模型,基于带悬挑平屋盖风压分布风洞试验数据,对三种加固足尺子结构试验模型进行不同风向角下风荷载时程的加载。分析结构风致加速度与位移响应,结果表明:附加杆件加固后网架刚度增大,加速度响应增大,位移响应减小;附加粘弹性阻尼器,结构加速度与位移响应均降低;附加粘滞阻尼器,结构加速度响应减小,位移减小效果不明显。

There are always larger wind-induced responses at edges of long-span grid roofs and it is hereby proposed three approaches to reduce vibrations,which are attached bars,viscoelastic damper and viscous damper.With the designs and manufactures of full scaled pyramid space truss model,on the basis of wind tunnel test data for wind pressure distributions at cantilevered flat roofs,the experiment implements wind load time history in different reinforcement ruler structures under different angles of wind direction.By analyzing acceleration and displacement reactions of experimental model,it is concluded that:with application of attached bars,structural stiffness is reinforced,acceleration response is increased,displacement reaction is reduced.With application of viscoelastic damper,structural acceleration and displacement responses are both reduced.With application of viscous damper,structural acceleration response is reduced,while the effect of displacement reduction is limited.