地铁引起邻近建筑物楼板的振动及简易预测方法

Analysis and Prediction of Train-induced Floor Vibration in Adjacent Buildings

为便于对地铁引起的邻近建筑物楼板的振动进行分析及预测,提出了简化计算方法。将楼板简化为单自由度体系,将地铁引起的建筑物内房间墙根的竖向振动加速度时程作为该单自由度体系的基底输入,即可求得体系的加速度响应,将此近似作为该房间楼板中间的振动响应。对上海地铁8#线引起沿线某六层砖混结构的振动进行实测,并用冲击法实测了楼板的自振频率和阻尼比。用文中建议的简化计算方法和有限元方法算得地铁引起的楼板中间的振动并和实测结果进行对比,验证了简化算法的可行性。

In order to better predict and analyze the train-induced floor vibration in adjacent buildings, a sim- plified method is suggested. First of all, the slab was simplified as a single-degree-of-freedom system. Then the vibration response in the middle of slab was obtained based on the vertical acceleration time-history at the bottom which is excited by the subway train. In the paper, in situ vibration measurements were performed on a six-floor masonry structure adjacent to the Shanghai No. 8 subway line. For the purpose of obtaining the nat- ural vibration frequency and damping ratio of the slab, an impact vibration test was also applied in the meas- urements. The suggested simplified method as well as FEM were employed to calculate the response in the middle of the slab. The analytical results obtained shows reasonable conformity with the measurements.