交通环境振动明沟减振效应的边界元模拟与分析

Simulation and Analysis on Open Ditch Damping Effect of Traffic Induced Environmental Vibration by Boundary Element Method

基于上海市某公路交通环境振动实测结果,验证了半平面分层土介质格林函数结合边界元原理,分析交通环境振动明沟减振效应的可行性,并探索了明沟的设计参数对减振效果的影响。研究结果表明:(1)所提的边界元法可很大程度节省明沟的建模工作量;(2)明沟是通过反射土层的面波振动能量达到减振目的,主动与被动减振措施均具有明显控制效果;(3)明沟深度是影响其减振效果重要因素,但并非呈现一致性,存在合理深度范围问题;明沟宽度与减振效果作用关系不明显;(4)由于弹性波的振动能量沿土层深度方向存在扩散,被动减振措施相对于主动减振措施对明沟的深度提出了更高的要求。

Based on the measurements of the traffic induced environmental vibration on a highway in Shanghai, this paper validated the principle of Green＇s function of half planar layered soil media combining with boundary element, analyzed the feasibility of open ditch damping effect thereof, and discussed the influence of the design parameters of the ditch on the damping effect. The results show that, （ 1 ） the boundary element method herein may make the ditch modeling convenient; （2） the open ditch may reduce the vibration by reflecting the vibration energy of surface wave of the soil layers, both active and passive damping measures have obvious result of control ; （3） the depth of the ditch is the important factor affecting the damping effect, however, it doesn＇t present a consistency, but a proper range, and the width thereof has unapparent relation to the damping effect ; （4） as the vibration energy of elastic wave is diffused in the direction of soil depth, measures, compared to the active ones, has more strict requirement on the depth of the the passive damping open ditch.