Study On Vibration Propagation Characteristics Of Soil Layer Under Excitation Of Subway

Subway transportation system,one of main city traffic methods,has many obvious advantages. In resent years, subway transportation systems have been developed rapidly in China.However,with the development of subway construction, some negative effects also appear.One of the serious problems is the impact of vibration induced by subway train to environment. Subway is a kind of powerful and rapid traffic way in big city and very effective to alleviate the traffic pressure.but subway can produce serious vibration and noise in its operation ,and bring out sub-structural noise and vibration of building along the line .this is a kind of serious pollution to urban environment,and sometimes affects the people's working and living condition neaeby. This vibration is called a social effects of pollution and should be controlled.Based on interpretation and analysis of home and foreign relevant research,for the purpose of reducing the vibration of adjacent buildings induced by subway,the characteristics of buildings vibration induced by subway are studied.Based on the research work before, firstly, The research results and situations about environmental vibration indueed by loads on subways at home and abroad have been summarized.Then,based on the relevant research production,we analyze the characteristics of adjacent buildings vibration induced by subway.A series of theoretieal knowledge and resolving methods in the process of numeric simulation has been represented,including the establishment of the function,the comprehension of the arithmetic,the choice of the elements,the modeling of the soil's boundary, the confirm of the dam Pete. This work offers a concrete basic for the following chapters.Using the Finite-element software ANSYS,two dimensions soil-tunnel model is established, and the dynamic response are analyzed in situation.At last,the characteristic of subway vibration is concluded,which could be used for for reference in vibration control and buffer design of the ground structure.Most importantly,by using the Tunnel Size soil and characteristics of Beijing subway line 5. two-dimensional dynamic finite element model has been derived in the circular tunnel and the rectangular tunnel. we also compare and analysis the two models which can be used in tunnel engineering design.