铁路振动作用下双排桩屏障隔振性能试验研究

为研究铁路应用双排桩屏障的隔振性能，基于铁路振动产生的弹性波传播特性，通过场地试验测得激振频率10Hz下地表振动加速度幅值，以双排隔振桩屏障中归一化桩间距、归一化排间距、排桩数量以及排桩布置形式为变化参数，研究改变双排桩几何参数对其隔振效果的影响。试验结果表明：随桩间距的增大，排桩屏障的隔振效果逐渐减弱。当归一化桩间距不小于3.0时，排桩屏障逐渐失去其整体隔振作用；当归一化排间距为3.0时，排桩屏障可以获得较优的隔振效果，其有效隔振面积百分比在19.52%~68.89%；随着排桩数量的增加屏障有效隔振面积随之增大，排桩数量由8增至10时，有效隔振面积百分比增大0.87%~4.74%，可以使更大区域范围达到隔振要求；当屏障整体桩数相同时，采取菱形布置形式的隔振屏障比矩形的隔振效果好，菱形布置较矩形布置有效隔振面积百分比增加1.20%~5.01%。

Experimental study on vibration isolation performance of double row pile barrier under railway vibration

In order to study the vibration isolation performance of double row pile barriers for railway applications, based on the propagation characteristics of railway vibration induced elastic wave, the amplitude of surface vibration acceleration was measured at a specified frequency of 10 Hz through field tests. The normalized pile spacing, normalized row spacing, number of piles and arrangement of row piles in the barrier of double row vibration isolation pile were taken as the research parameters. The influence of geometric parameters of double row piles on its vibration isolation effect was studied. The test results show that with the increase of pile spacing, the vibration isolation effect of pile barrier decreases gradually. When the normalized pile spacing is not less than 3.0, row pile barrier gradually loses the effect of overall vibration isolation; when the normalized row spacing is 3.0, the row pile barrier can achieve better effect of vibration isolation, and the effective percentage of vibration isolation area is 19.52%-68.89%;with the increase of piles number, the effective vibration isolation area of the barrier increases, and increased the number of piles from 8 to 10, the effective vibration isolation area percentage increases by 0.87%-4.74%, which can make the larger area meet the requirements of vibration isolation; when the total number of barrier piles is the same, the rhombus shape vibration isolation barrier is better than the rectangular vibration isolation effect, and the percentage of effective vibration isolation area increased by 1.20%-5.01% compared with the rectangular arrangement.