铁路环境振动对厂房内精密仪器的影响分析

摘要

以龙烟铁路沿线厂房内的精密仪器为研究对象,利用有限元法,建立轨道-桥梁及桥墩-基础-土体计算模型,计算货车在不同运行速度下引起的大地振动响应,得出振动加速度、速度及位移沿距离的衰减规律,分析铁路环境振动对铁路沿线厂房内精密仪器的影响.研究表明:列车速度对振动响应的影响较大,速度越高,地面上相同位置上的振动响应越大；振动加速度、速度和位移沿距离的衰减特性基本一致,呈现指数曲线的衰减规律；若不考虑精密仪器的自身隔振能力,两列货车以120 km/h和100 km/h的速度在精密仪器附近交会时,加速度、位移及y方向的速度预测值满足仪器振动限值要求,x和z方向的速度预测值超出了仪器振动限值要求；考虑精密仪器自身基础的隔振能力后,振动预测值均满足仪器振动限值要求.%The reliability of precision instruments inside the plant along Longkou-Yantai railway was taken into account.In order to calculate the ground vibration response caused by freight trains with different speeds,a model of track-bridge together with pier-foundation-soil was established by using finite element method.The attenuation of vibration acceleration,velocity and displacement at positions with different distances apart was investigated and the effect of railway environment vibration on the reliability of precision instrument inside the plant was analysed.The results show that the train speed is of great influence on vibration response,the higher the train speed,the greater the ground vibration response at the same location.The attenuation characteristics of acceleration,velocity and displacement at different distances are substantially uniform and obey the rule of exponential.Without considering the precision instrument's own isolation capability,when two freight trains with the speed of 120km/h and 100km/h respectively meet at the place near the factory plant,the predicted values of acceleration,displacement and Y direction velocity are less than the vibration limit values for instruments,but the predicted X and Z direction velocities are beyond the limit values.If considering the precision instrument's own isolation capability,the predicted vibration values can all meet the specified requirements of working condition for precision instruments.