三向地震荷载作用下地铁车站结构的动力响应特性

Dynamic response characteristics of subway station structure under three-dimensional seismic load

为确保地震发生时地铁车站结构的安全性,建立土体-地铁车站-轨道相互作用的三维精细化计算模型,分别输入水平单向地震波和三向地震波,探究地铁车站重要组成结构的应力、位移及加速度响应特性,对比分析两种地震形式下车站主体结构响应的异同。研究结果表明:两种工况下,柱结构应力值最大,三向地震工况下柱结构应力峰值响应较水平单向地震工况时显著增大,下层柱底部所受应力峰值最大;三向地震工况下中线处较早达到最大相对水平位移峰值,中线处相对水平位移大于其他位置相对水平位移,三向地震工况下相对水平位移大于水平单向地震工况下相对水平位移,且变化更为复杂;三向地震工况下各板的水平加速度峰值响应较水平单向地震工况时显著增大,顶板加速度放大系数最大,故各层板中顶板受地震影响最为严重。

To ensure the safety of subway station structures during earthquakes,a three-dimensional refined calculation model for the interaction between soil,subway stations,and tracks was established.Horizontal unidirectional seismic waves and three-dimensional seismic waves were input respectively to explore the stress,displacement,and acceleration response characteristics of important components of subway stations.The similarities and differences in the response of the main structure of the station under the two types of earthquakes were compared.The research results indicate that under both working conditions,the stress value of the column structure is the highest.The peak stress response of the column structure under three-dimensional seismic conditions significantly increases compared to that under horizontal unidirectional seismic conditions,and the stress peak at the bottom of the lower column is the highest.Under three-dimensional seismic conditions,the maximum relative horizontal displacement peak is reached earlier at the centerline,and the relative horizontal displacement at the centerline is greater than that at other positions.The relative horizontal displacement under three-dimensional seismic conditions is greater than that under horizontal unidirectional seismic conditions,and the changes are more complex.The peak response of horizontal acceleration of each plate under three-dimensional seismic conditions increases significantly compared to that under horizontal unidirectional seismic conditions,and the amplification coefficient of top plate acceleration is the highest.Therefore,the top plate is most severely affected by the earthquake.