高速铁路客站大跨站厅结构竖向多点地震响应研究

Vertical seismic response of long-span hall of high-speed railway station under multi-point earthquake excitations

"房桥合一"是我国高速铁路客站建造中出现的一种新型结构形式,其兼具房屋和桥梁结构特征,轨道层列车线路的通行要求决定了上部高架站厅层具有较大跨度,而站厅结构竖向抗震性能往往是确保其地震安全的重要部分。鉴于此,首先阐述了SAP2000软件中位移模型的基本计算原理,并指出其一重要误差,继而参考天津西站建立了典型大跨站厅结构模型,对比研究了竖向多点一致、考虑行波效应竖向多点非一致地震激励下典型站厅结构动力响应特征。研究表明:依据位移模型直接计算结果来获取不参与动力平衡方程的从属结构响应分量时可能存在明显误差;竖向多点非一致输入特征对高架站厅层的地震响应有着显著影响,在抗震设计和性能评估中均不可忽视此因素,同时给出了抗震设计建议。

The vertical seismic performance of the long span hall in high-speed railway station is often the weak link under earthquake.In view of this,the basis principle for response calculation of the displacement input model in SAP2000 software was introduced,and the Tianjin West Railway Station was referred to establish the structured model of a typical station hall.Seismic response characteristics of the typical station hall under uniform,multi-point time history excitations and random earthquake excitations in consideration of travelling wave effect were studied.The results show that： utilizing response results calculated by using displacement model to solve the structural response components of subordinate structures,not involved in the dynamic equilibrium equation,may produce obvious error.The feature of multi-point input has a significant impact on vertical seismic response of elevated station hall,which should not be ignored in the seismic design and performance evaluation.Appropriate seismic design recommendations were also given in the paper.