地铁抗震设防水准的研究及北京地铁工程典型地段地震小区划

地铁作为人口密集且遭受地震破坏后难以修复的重要生命线工程,如何确保其地震安全具有越来越重要的意义。本文将以北京具有典型意义的地铁线路———北京地铁五号线作为研究目标,在对沿线地震、地质条件分析的基础上,通过分析研究在不同场地条件、不同风险水平和不同深度条件下的地震动参数和反应谱变化规律,确定了地铁工程的抗震设防概率风险水平为50 a超越概率63%、10%、2%,设计地震动参数取地表计算值。并通过北京地铁五号线工程地震小区划及分区反应谱特征研究,确定北京地铁五号线工程的抗震设防要求。

SUBWAY EARTHQUAKE FORTIFICATION LEVEL AND SEISMIC MICROZONING FOR TYPICAL SUBWAY ZONES IN BEIJING

With the rapid development of major cities,Subway line has become an important traffic transportation in major cities.A subway line is an important and densely populated lifeline infrastructure.It is difficult to renovate it if a subway line is damaged during earthquake.Therefore,it has become more and more important in ensuring subway safety during earthquake.In this paper,based on the fifth subway line in Beijing,the relationships of ground motion parameters and response spectrums in different site conditions,different risk levels and different depths are discussed.It is determined that the 50 year exceedance probability 63%、10%、2% can be used as the subway earthquake fortification levels.The surface ground motion parameter can be used as the design ground motion parameter.Through studying seismic microzoning and response spectrum characters,this paper defined the earthquake fortification level for the fifth subway line.