三维倒虹吸结构动力响应分析

倒虹吸结构广泛应用于我国农田水利建设、城市供水、大型调水工程中,很大一部分倒虹吸结构处于高烈度地震区,不可避免遇到抗震问题。考虑土与倒虹吸结构的相互作用,建立三维有限元模型进行静力分析,并在此基础上进行倒虹吸结构动力时程分析,研究倒虹吸结构在动力作用下的工作性态。通过比较加速度、位移及应力3方面的响应情况,发现地震作用下,加速度沿倒虹吸截面高度变化不大,y向位移相对x及z向较大,各向应力的增幅较小,7级地震作用下倒虹吸结构是安全的。

Analysis on Dynamic Response of 3-D Inverted Siphon Structure

Inverted siphon structure is widely used in China’s farmland water conservancy construction,city water supply,and large water diversion project.But seismic problems are inevitably encountered because a large part of inverted siphon structures are located in regions of high seismic intensity.A three-dimensional finite element model in consideration of the interaction between soil and inverted siphon structure is established to conduct static analy-sis.On this basis,the working performance of inverted siphon structure under dynamic action is researched through time-history analysis.By comparing the responses of acceleration,displacement and stress,we concluded that there is little change in the acceleration along the sectional height of inverted siphon,and the displacement in direction y is larger than that in direction x and z,and the increment of stress is not large in all directions.The inverted siphon structure is safe under earthquake of magnitude 7.