一格构式广播电视发射塔抗震性能分析  

Seismic Performance Analysis of a Tall TV and Broadcasting Lattice Tower

作　　者：万月荣[1] 

机构地区：[1]同济大学建筑设计研究院(集团)有限公司,上海200092

出　　处：《特种结构》2014年第4期53-56,100,共5页Special Structures

摘　　要：通过对一结构立面复杂的广播电视发射塔结构进行非线性数值模拟,全面研究了其抗震性能。由结构特征值分析可知,结构第一扭转振型出现在第8阶振型中,结构第一扭转周期与第一平动周期之比为0.197,满足相关规范要求。继而采用静力分析手段,计算了结构在多遇地震作用和风荷载下的位移响应。通过静力计算可知,结构天线顶点和塔体主结构顶部的层间位移均小于相应规范中规定的层间位移角限值;且与地震荷载相比,风荷载对结构起控制作用。通过结构非线性时程分析可知,在多遇地震作用下,结构构件均处于弹性阶段,结构层间位移较小;在罕遇地震作用下,虽结构的层间位移有所增大,但绝大多数结构构件仍处于弹性阶段,结构具有较好的抗震性能。This paper presented a nonlinear numerical analysis on the seismic performance of a tall steel TV and broadcasting lattice tower structure. Modal analysis was conducted to investigate the vibration modes of the tower structure. It was noted that the ratio between the natural period of the first translational vibration mode and that of the first torsional vibration mode was 0.197. Static analysis was then conducted to study the inter-story drifts of the tower structure under frequently occurred earthquake and wind load. The inter-story drift responses were found to be smaller than the drift limit in accordance with relative code provisions. It was also noted that when comparing with earthquake action, wind load had a more dominant influence on the drift response of the tower structure. Nonlinear time-history analysis was also used in this study to evaluate the seismic displacement response of the tower structure. It was noted that all the structural members were still in the elastic range under the frequently occurred earthquake, and the tower structure behaved in a ductile manner under the rarely occurred earthquake. Results in this paper may provide recommendation, as well as engineering assessment for the structural design of the tower structure.

关 键 词：高耸结构 抗震性能 层间位移 非线性时程分析 

分 类 号：TU352.11[建筑科学—结构工程]