空间钢桁架伞撑空冷支架结构多维地震反应分析

Analysis on Multi-dimensional Seismic Response of Space Steel-truss Steel-brace Air-cooling Condenser Structure System

针对火力发电厂机组容量的不断增加,钢桁架管柱空冷支架结构在高烈度区已很难满足结构性能要求的实际情况,提出了一种新的结构形式—空间钢桁架伞撑空冷支架结构,以此建立空间有限元模型分析结构的动力特性。在三条地震波输入下,分别计算结构的层位移、层间位移角及层剪力,对比双向水平地震动和多维地震动的计算结果,提出结构扭转作用比及考虑扭转地震动作用的调整系数。考虑到扭转地震动对结构的影响,建议对水平地震动计算得到的地震作用乘以增大系数。

As the increasing of the unit capacity in a power plant, the steel-truss RC pipe-column air-cooling condenser structure system in a high seismic intensity zone could not match the request of structure capability, so a new structural system--the space steel-truss steel brace air-cooling condenser stucture system is brought up as a solution. Here taking the space steel-truss steel-brace air-cooling condenser structure system as a research objecct, a space finite element model is built to analyze its dynamic properties. Its layer displacement, inter layer displacement angle and layer shear are cal- culated under three seismic waves respectively, the calculation results of two-direction level seismic-wave with muhi-di- mensional seismic-wave are compared, then, the torsional earthquake effect ratio and adjusting coefficient are suggested. Considering the impact of torsional seismic-wave on the structure, it is recommended that the earthquake effect of two-direction level seismic-wave is multiplied by the earthquake amplification factor.