大跨度张弦桁架结构自振特性和地震响应分析

为了研究大跨度张弦桁架结构的自振特性及其地震响应,首先应用有限元方法对结构的振型进行分析,然后通过时程分析法讨论张弦桁架结构在地震作用下的动力响应,主要研究了不同预应力、撑杆数、拉索横截面积及约束条件对其自振特性和地震响应的影响以及不同地震波对结构响应的影响。分析结果表明,张弦桁架结构的低阶振型以竖向振动为主,预应力、撑杆数、拉索横截面积对低阶振型影响很小,对结构的地震响应影响也很小;但约束条件对结构的低阶振型影响很大,对结构的地震响应影响也很大;结构的响应还与地震波有很大关系。

Analysis of free vibration characteristics and seismic response of long-span truss string structure

In order to study the free vibration characteristics and seismic response of long-span truss string structure, the vibration mode analysis is firstly carried out for this structure through finite element method, then time history analysis is performed to study the dynamic behavior of truss string structure under earthquake action, the study mainly includes the effect of prestress of cable, number of struts, area of cables and restrictions on free vibration characteristics and seismic response, and also includes the effect of different wave on seismic response. The results show that low vibration modes of the structure are mostly vertical modes. The effect of prestress of cable, number of struts, area of cable on the low vibration modes and seismic response of long-span truss string structure is slightly. But the effect of restrictions on the low vibration modes and seismic response of this structure is largely. The response of structure has much to do with the waves.