Study On The Law Of Metro Vibration Propagation And Its Influence

The subway has a great contribution to the development of the city and bring convenience to the public.However,the vibration problem caused by the subway has attracted more and more attention.So It has profound practical significance and social significance on solving the vibration problems to analyze and study the laws of subway vibration propagation.In this paper,the influence and mechanism of metro vibration are analyzed,based on the test data,the finite difference software FLAC3 D is used to analyze the subway viration.In this paper,the main study contents and conclusions are as follows:（1）This paper describes the mechanism of the vibration load induced by subway transit: train factors and track factors can lead to vibration load,especially track irregularity,which is the main factor of vibration load.The discrete sampling value of field track vibration acceleration wave is transformed by Matlab program and analyzed by deterministic analysis.A simplified vehicle model is established.Then through dynamic analysis,the dynamic balance equation of the wheel&rail interaction is derived,and the load expression as well as the time history of vertical vibration induced by subway train operation are determined by solving problems.（2）FLAC^3D is applied to simulate the vibration response of subway.Compared with results of different conditions,The law of the ground vibration caused by different frequency load is analyzed,and the influences of tunnel form,tunnel depth,soil condition and other factors on the ground vibration response are discussed qualitatively.The location of vibration amplification area is related to the source,tunnel depth,soil condition and other conditions.（3）The examples used are to illustrate the influence on buildings,human bodies and precision instruments caused by subway vibration.Long term vibration load on the building structure will cause the building structure of the dynamic fatigue and stress concentration,reduce the strength of the structure of the building,and lead to cracking or deformation of the structure.If the situation is serious,it will affect the daily use and maintenance of the building structure.The influence of environmental vibration induced by subway on the human body is to harm human health,interfere with daily life,reduce work efficiency and so on.Environmental vibration induced by subway will also have a certain impact on the use and production of precision instruments and equipments.