列车运行对周围地面振动影响的试验研究

Experimental study of ground vibrations induced by moving train

针对日益严重的轨道交通引起的环境振动问题,通过对京―广铁路线附近某小区内地面的竖向、横向振动速度和加速度的现场测试,研究了运行列车引起的地面振动及其传播规律。由试验分析可知,列车引起的地面振动速度、加速度振级均随着列车速度的提高和轴重的增加而增大。速度每小时提高10km时,速度振级和加速度振级均增大约3dB;车速相同的货车比客车引起的速度振级竖向大10dB左右,横向大5～15dB左右;加速度振级竖向大12dB,横向大8dB。钢轨接缝附近地面的振动比无接缝附近的地面振动大,速度振级大2～6dB。振动随着距振源距离的增大而逐渐减小,竖向振级的衰减过程表现出一定的波动性;横向振级的衰减随距离增大单调减小。

To study more and more serious vibrations problem induced by moving train traffic in urban areas, in a residential district near Jing-Guang Railway, field tests of velocity and acceleration vibrations of ground were carded out during train moving; and some conclusions were drawn. It is shown that the vibrations of ground due to moving train rise with train speed or axle load increasing. Generally, when speed of train increases 10 km per hour, the vibrations level raises 3 dB, while at the same speed, vibration induced by freight train is bigger than passenger train because of the difference of axle load. In the test, at speed of 50 km per hour or so, the vertical velocity vibration induced by freight train is about 10 dB bigger than that of passenger train, and as for the difference of lateral velocity vibration, this magnitude is about 5 to 15 dB; moreover, as for the difference of vertical and lateral acceleration vibrations, they are 12 dB and 8 dB respectively. The vertical velocity vibration of ground near the joints of rails is 2 to 6 dB bigger than the other positions far from joints. Ground vibration decreases gradually with increasing in the distance between testing locations and rail; and there is a fluctuated characteristic of the decay process for vertical vibrations; while the lateral vibration decreases monotonically with increasing in the distance between testing locations and rail.