地铁车辆段上盖建筑车致振动试验

为了研究地铁车辆段上盖建筑车致振动机理,对杭州某地铁车辆段试车线上盖建筑的振动进行了试验研究。基于环境激励分析了上盖建筑楼板的动力特性,研究了不同车速下地铁车辆段上盖建筑的车致振动特性和传播规律,结合中国环境振动评价标准对建筑物室内的振动舒适度进行了评价。结果表明:上盖建筑楼板一阶频率在28～46 Hz之间,阻尼比为0.3%～1%; 上盖建筑物的车致振动主要分布于0～140 Hz之间,10～25 Hz以内的低频振动表现为结构的整体振动,沿层高有放大的趋势,不同车速下楼板振动频率分布类似,都主要集中在楼板的自振频率附近; 随列车加载车速的降低,地铁上盖建筑中的整体振动强度呈下降趋势,部分楼板的最大Z振级及分频振级均出现“反弹”现象; 试车线列车以超过35 km·h^-1的车速运行时上盖建筑中楼板的实测最大Z振级超过了标准限值,为保证试车线列车功能同时提高上盖建筑的振动舒适度,有必要在已有轨道减振的基础上对上盖建筑物进一步采取减振隔振措施。

Train-induced Vibration Test of Metro Depot Over-track Buildings

In order to study the vibration mechanics of metro depot over-track buildings caused by the train,the vibration test of the metro depot over-track building on the test line in Hangzhou was carried out. Based on the environmental excitation, the dynamic characteristics of the superstructure floor were analyzed, and the vibration characteristics and propagation laws of the subway superstructure floor at different train speeds were studied. The vibration comfort degree of building interior was evaluated according to the Chinese environmental vibration evaluation standard. The results show that the first-order frequency of the floor of the over-track building is between 28-46 Hz, and the damping ratio is 0.3%-1%. The train-induced vibration of the over-track building is mainly distributed between 0-140 Hz, and the low frequency vibration within 10-25 Hz is the overall vibration of the structure, and there is a trend of amplification along the floor height. The distribution of floor vibration frequency is similar under different train speeds which is mainly concentrated near the floor vibration frequency. With the decrease of train loading speed, the overall vibration intensity of over-track building decreases, and the maximum Z vibration level and the frequency division vibration of some floors are rebounding. When the train on the test line runs at a speed of more than 35 km·h^-1, the measured maximum Z vibration level of the floor in over-track building exceeds the standard limit value, so as to ensure the test function of the test line and improve the vibration comfort of the over-track building. It is necessary to take further vibration reduction and isolation measure for the metro depot over-track building on the basis of the existing track vibration reduction.