交通荷载作用下不同场地微振动响应及衰减规律分析

Analysis of Attenuation Law of Micro-vibration Response in Variable Sites under Traffic Loads

随着高科技电子产业的蓬勃发展,车辆行驶对高科技电子厂房产生的微振动影响逐渐引起人们的关注。为研究交通荷载作用下不同场地的振动响应及衰减规律,对上海、北京、太原3个场地进行振动原位测试和分析。研究发现:相同振源在不同场地引起的振动响应及衰减速度不同,场地土越软,引起的振动响应越大,地面振动衰减速度越慢;频谱峰值对应频率随场地土硬度增大逐渐增大;高频信号振动衰减速度大于低频信号,低频信号传播距离较高频信号更远。在卡车以20 km/h车速行驶工况下,中软土、中硬土场地距路中心60 m以后的测点场地振动水平低于VCD水平,适于布置电子厂房。对于软弱土场地,距路中心150 m的测点场地振动水平依然大于VC-D水平,需要考虑低频振动隔振。

With the vigorous development of the high-tech electronics industry,the micro-vibration effects of traffic and road vehicles on the high-tech electronics factory are gradually attracting people′s attention.In order to study the vibration response and attenuation laws of different sites under traffic loads,in-situ vibration tests and analysis are carried out on three sites in Shanghai,Beijing and Taiyuan.The study found that the vibration response and attenuation speed of the same vibration source at different sites are quite different.The softer the site soil,the greater the vibration response and the slower the ground vibration attenuation speed;The frequency corresponding to the peak of the frequency spectrum gradually increases with the increase of soil hardness;The vibration attenuation speed of high-frequency signals is greater than that of low-frequency signals,and low-frequency signals propagate farther than the higher-frequency signals.At a truck speed of 20 km/h,the vibration level of the measuring point beyond 60m from the road center is lower than the VC-D level in the medium-soft soil and medium-hard soil sites,which is suitable for constructing electronic workshops.For soft soil sites,the vibration level of the measuring point 150 m away from the road center is still higher than the VC-D level,so low-frequency vibration isolation needs to be considered.