某水电站进水塔地震作用下鞭梢效应分析

Analysis of Whiplash Effect of a Hydropower StationIntake Tower under Earthquake

采用时程法计算地震作用下某进水塔的动力特性,提取顶部排架柱的动力响应结果,分析顶部结构在地震作用下鞭梢效应所带来的放大增幅以及出现原因。分析结果显示:塔顶排架柱迎水向存在明显的鞭梢效应,动力响应规律与传统高耸结构相似,其中拦污栅排架柱顶部位移响应相对底部放大了2.02倍,加速度响应变化幅度达到84.18%;启闭机排架柱位移响应放大了2.58倍,加速度响应放大了2.2倍。

In this paper,the time history method is used to calculate the dynamic characteristics of an intake tower under earthquake.The dynamic response results of top bent columns are extracted,and the amplification and reasons of whiplash effect of top structure under earthquake action are analyzed.The analysis results show that:there is obvious whiplash effect in the upstream direction of the bent column on the top of the tower,and the dynamic response law is similar to that of the traditional high-rise structure.The displacement response of the top bent column of the trash rack is enlarged by 2.02 times compared with the bottom,and the acceleration response changes by 84.18%;the displacement response of the crane bent column is amplified by 2.58 times,and the acceleration response is enlarged by 2.2 times.