反应位移法在地铁隧道抗震分析中的应用

Application of response displacement method in the seismic analysis of subway tunnel

高烈度地区进行地铁建设活动,隧道的抗震性能研究是必要的工作。反应位移法是《城市轨道交通结构抗震设计规范》的推荐方法。拟通过具体算例分析,探讨目前反应位移法在实际应用中需关注的问题。计算分析表明:地震作用等级、场地类别、覆盖层厚度等因素导致地震响应差别显著;土层位移对结构内力贡献最大,结构周围剪力次之,惯性力影响最小;高烈度地区,准永久组合计算结果不满足地铁隧道截面抗震验算要求。

Investigation on subway tunnel's seismic analysis is necessary work in high earthquake intensity regions.Response displacement method is recommended by 'code for seismic design of urban rail transit structures'.Several problem in response displacement methods were investigated based on some specific examples in this paper.The analysis results showed that:There were large differences between earthquake function grade,site classification and overburden thickness;Soil displacement greatest contribution to the structure of the internal forces,shear force,followed by the surrounding structures,with minimal impact inertia force;Typically,the calculation results of quasi-permanent combination cannot meet subway tunnel seismic requirements.