大型渡槽支座隔震研究

Seismic isolation of large aqueduct by using seismic isolation bearing

采用数值模拟和实验研究了某大型渡槽采用球形减震支座的减震效果及减震机理。振动台实验和数值模拟的结果都表明:所设计的不同的减震支座对结构均有减震效果,槽身主要测点动应力值明显减小;采用减震支座后,不同周期的地震波减震的效果虽然有差别,但主要部位动应力都有比较明显的减小;结构的水平向加速度也明显下降。从减震支座的滞回曲线看,横槽向和顺槽向均有比较明显的滞回环,说明球形减震支座具有比较明显的耗能效果,这也表明该支座对大型渡槽的减震有效果。减振支座的相对位移较小,可以满足设计要求。从这些结果看:大型渡槽采用减震支座是可行的,而且减震效果明显。

The vibration-isolating mechanism of a large aqueduct with seismic isolation spherical bearings and its effect are investigated by using experiment and numerical simulation methods. The results show that all designed bearings with different parameters are effective in decreasing obviously the peak values of dynamic stresses of the structural during earthquake as well as the accelerations in two horizontal directions, and hysteresis rings are clear on horizontal plane, namely, energy dissipation is obvious. Though different earthquake waves with different dominant frequency are input, the measured dynamic stresses still get down more or less. The relative displacement of the bearing is small enough to meet design requirement of the bearing. The conclusion from the results is that it is feasible to utilize seismic isolation bearing in design of large aqueduct and the aseismic effect of the bearing is obvious.