【摘要】 建立一个大跨越钢管混凝土输电线路的单塔和塔线体系有限元模型,对这两种模型进行地震响应分析。首先,利用振型分解反应谱法分析两种模型在地震作用下的响应;然后,选取两条实际地震波和一条人工波,利用时程分析法获得两种模型在三种地震波作用下的响应。计算表明:塔线体系的固有频率与单塔相比变化很小;由于输电线的减振作用,塔线模型的底部剪力和一些单元的应力比单塔模型的有所减小;由功率谱法指出结构的一阶模态对结构的地震响应起决定性作用;时程法得到的结构底部剪力均不小于反应谱法的80%,说明所选的这组地震波是合适的。反应谱法与时程分析法计算的结果具有较好的可比性,说明采用的计算方法、过程和结果是有效的。更多还原

【Abstract】 FEM models of a single concrete filled steel-tube tower and a long-span transmission tower-line system were established to analyze the seismic responses.The seismic behaviors of the two models were studied first by using mode-decomposition response spectrum method.Then,two seismic records and an artificial seismic wave were selected to analyze the seismic behaviors of the two models by using time-history analysis method.The results indicated: ①the natural frequencies of the tower-line system were very similar to those of the single tower;②the tower-line system developed smaller axial stresses in some members and smaller shear forces on supports than the single tower because of the wires acting as a tuned mass damper;③the power spectrum analysis revealed that the seismic responses of the structure were mostly dominated by the structural first-order mode;④the seismic results obtained from the response spectrum method and time-history analysis method were in good agreement.更多还原