场地⁃隧道⁃地上建筑结构体系地震响应的振动台试验

Shaking Table Test of Seismic Response of Site⁃tunnel⁃aboveground Building Structure System

在土体⁃结构体系动力响应研究中,输入地震动特性是必须考虑的关键因素。分别考虑地震动的频谱特性差异和速度脉冲特征,选取了两条不同类型的地震动加速度记录及一条人工合成地震动时程作为输入地震动,设计并开展了隧道与地上建筑结构体系模型的振动台试验,基于试验数据分析了地震动频谱与速度脉冲特性对隧道与地上建筑结构动力响应的影响。结果表明:场地⁃隧道⁃地上结构体系地震响应中,隧道与地上结构的相互作用效应显著,地上结构的存在对地下隧道地震响应的较高频响成分有更显著的影响;相互作用效应显著地受到场地输入地震动频谱特性的影响;输入地震动的速度脉冲特性对隧道响应的影响主要表现在较高频范围,而对地上结构响应的影响不只表现在较高频范围,对周期1.0~2.0的频率范围的响应也具有明显增大作用。

In the research of the dynamic performance of the soil-structure system,input ground motion characteristics are key factors that must be considered.In this study,the shaking table test was carried out on the structure system model of the tunnel and aboveground building under different seismic inputs,including two seismic acceleration records with different frequency spectra and an artificial ground motion time-history.The influence of the spectra and the velocity pulse characteristics of earthquake ground motion on the dynamic response of the tunnel and the aboveground building structure was analyzed.The results indicate that for the seismic response of the site-tunnel-aboveground structure system,the interaction effect between the tunnel and the aboveground building is significant,and the existence of the aboveground building has a more significant impact on the higher frequency component of the seismic response of the underground tunnel;the interaction effect is significantly affected by frequency spectra of the input ground motion;the influence of the velocity pulse characteristics of the input ground motion on the tunnel response is mainly in the higher frequency range,while the influence on the response of the aboveground building is not only in the higher frequency range,but also significant to increase the response in the frequency range of period 1.0 s to 2.0 s.