移动车辆荷载环境微振动的排桩隔振参数分析

Vibration Isolation Parameters of Piles in Micro-vibration Induced by Moving Vehicle Load

摘要:

为满足精密仪器振速控制要求，提出"群桩基础+隔振排桩"与空气弹簧的两级组合隔振措施。主要研究路面移动车辆荷载经过时，第一级隔振中排桩的隔振效果。实测土体小应变动力参数，通过编写车辆-路面耦合单元（VRI）子程序引入路面不平顺，并基于三维有限元法建立了道路-排桩-地基动力模型。将模拟振速经1/3倍频程滤波与实测进行对比，并对隔振排桩进行了参数分析。研究结果表明：两级隔振体系可满足VC-E微振动控制要求；排桩的间距、桩长和排数是影响隔振效果的主要因素，且竖向隔振效果较水平向好。研究成果可为今后环境微振动工程的设计与施工提供有益参考。

Abstract:

To meet the requirements of vibration speed control of precise instruments, a two-stage isolation measure combined by "group pile foundation + vibration isolation row pile" and air spring was proposed. This paper mainly studied the vibration isolation effect of row piles when moving vehicle passes. Dynamic parameters of the soil under small strain were first measured, then the road surface roughness was introduced by writing a subroutine of vehicle-pavement coupling unit (VRI), and a dynamic model of road-row pile-foundation was established based on the three-dimensional finite element method. The simulated vibration velocity was compared with the measured value through 1/3 octave filtering, and the vibration isolation parameters of piles were analyzed. The research results showed that the two-stage vibration isolation system can meet the control requirements of VC-E micro-vibration; The spacing and pile length of row pile, and the number of rows are the main factors affecting the isolation effect, and the vertical isolation effect is better than horizontal effect. The research results can provide useful reference for the design and construction of environmental micro-vibration projects in future.