地铁对周边建筑物振动影响分析

ANALYSIS OF EFFECTS INDUCED BY SUBWAY TRAIN ON SURROUNDING BUILDING VIBRATION

建立了土层系统-建筑物二维共同作用有限元模型,采用Newm ark隐式逐步数值积分法,从地铁列车荷载频谱特征和场地土层类型角度,分析了由地铁运行所诱发的周边建筑物振动响应规律。分析表明,在同一频率地铁振动荷载影响下,同一建筑物各楼层振动响应水平基本相同,上部楼层的振动仅比下部楼层振动有小幅上升;地铁低频段荷载对建筑物振动的影响大于高频段荷载的影响,但该低频段宽度要比建筑抗震分析中所考虑的地震荷载频段要宽;不同类型土层上建筑物的振动响应规律基本相同,表现为随建筑物距离地铁线路距离的增大,由地铁运行所诱发的建筑物的振动响应波动减小,但随土层硬度增加,建筑物的振动响应水平和衰减幅度也随之减小。

Based on Newmark's step-by-step implicit integration method,vibration response analyses of buildings due to nearby subway train running are studied with a 2D soil-structure finite element model from the views of subway train load spectrum characteristic and soil type.The analysis results show that vibration levels of different floors in a building are identical basically,and the vibration levels of the upper floors are a little higter than these of the lower ones;the vibration effects on surrounding buildings near the subway train induced by the subway-train low-frequency load are stronger than those by the high-frequency load;especially,the width of the low-frequency band is wider than that considered in the seismic analysis of buildings;the laws of vibration induced by subway train are identical basically when the buildings are on the different types of soil,and the vibration effects decrease in flutuation with the distance increasing between the subway train and the buildings;the vibration responses are the highest when the buildings stand on soft soil,but the vibration levels and the amplitude attenuation both decrease with soil hardening.