考虑温度影响的LRB隔震建筑地震响应分析

Seismic Response Analysis of LRB Isolation BuildingsConsidering the Effects of Temperature

摘要:

为研究温度对铅芯橡胶支座（LRB）性能的影响，进行支座拟静力试验。试验表明，在不同温度环境中试件的滞回曲线明显不同，支座的刚度和屈服剪力均随温度的升高而降低；低温时，支座的力学特性变化较大，而当温度大于20℃时，支座的力学特性趋于稳定。以某五层基础隔震建筑为例，编写基础隔震结构非线性时程分析程序NBIS，计算该隔震建筑在考虑温度影响后的地震响应。结果表明，在多遇地震作用下支座恢复力随温度的升高而降低，与罕遇地震下的变化趋势相反；考虑LRB温度影响后，该基础隔震结构的减震系数随环境温度的降低而增大，支座的最大位移随温度升高而增大。

Abstract:

A pseudo-static experiment was carried out to study the effect of temperature on the performance of a lead rubber bearing (LRB). Results showed that the hysteretic curves of the specimen was clearly different under different temperatures, and the stiffness and yield shear force of the bearing decreased with increasing temperature. At low temperatures, mechanical properties of the bearing varied greatly, but tended to be stable when the temperature was >20℃. Taking a five-story base isolation building as an example, a nonlinear time history analysis program NBIS for base isolated structures was compiled to calculate the seismic response of the building after considering the effect of temperature. Results showed that the restoring force of the bearing decreased with increasing temperature under frequent earthquakes, which was contrary to the changing trend under rare earthquakes. The seismic decrease coefficient of base-isolated structure increased with decreasing ambient temperature considering the effects of temperature, and maximum displacement of the bearing increased with increasing temperature.