均质地基地铁车站对临近建筑层间位移角的影响

Influence of Subway Station Buried in Homogeneous Foundations on the Inter-story Drift Ratio of Adjacent Structures

以软土、中软土和中硬土3种均质地基作为研究基准,采用广义层间位移谱,结合有限元计算模型,考虑场地类型和距车站水平距离两个影响因素,分析地铁车站的存在对临近建筑结构的动力影响.结果表明,在地震动作用下,地铁车站的存在将增加临近地表建筑结构的层间位移角,给结构的安全性和抗震性能带来不利影响;随着距离车站水平距离的增加,地铁车站的影响将逐渐减小.结合本文算例初步认为,在软土场地条件下,地铁车站的影响最为显著;同时给出不同场地条件下,地铁车站所能影响的区域范围以供参考.软土场地中,地铁车站对距离车站2.0倍车站水平宽度范围外的地表建筑的影响仍十分明显,需要妥善考虑;而在硬土场地条件下,当距离车站的水平距离超过1.5倍车站宽度时,车站的影响已可忽略.

Generalized inter-story drift spectrum,in which the existing structures are equivalently simplified as combined shear-flexural beams and the FEM models,was used to analyze the influence of a subway station,which was supposed to be buried in three types of homogeneous foundations respectively on the inter-story drift and anti-seismic performance of nearby buildings.It is illustrated that the existence of subway station will increase the inter-story drift of adjacent structures,which is harmful for the safety and the seismic performance;the influence of the subway station decreases gradually as the distance of the building to the subway station increases.According to the cases analyzed in this paper,the influence of the subway station is the most significant when the station is buried in soft site.Moreover,the approximate range of influence of the subway station in special site conditions were given and discussed：for the soft site condition,the buildings away from the station with a distance 2.0times the length of the station will still be affected;and in the hard site,the calculations obtained from the conditions with and without the subway station are almost the same when the distance equals to 1.5times the length of the station.