Analysis On Underground Subway Station Structure Under Seismic Dynamic Response

A large number of people coming from the countryside swarm into the city because of the rapid economic development and the huge foundational population.The main problem is that the space above the ground is too small to meet people's life,so it is necessary to focus our eyes on the underground space.However,the underground structure seismic damage occurred frequently and bring huge losses to people,has caused more and more researchers' attention.this work has researched mainly the Dangerous section of the subway station and the factors impacting on the subway station structure Under the seismic load,and at the same time,discussed the key problems existing in the earthquake response at length.(1)Taking Three Churches station of Shijiazhuang subway in progress for example,setting up three dimensional model and calculating Dynamic simulation.Introduce two kinds of dampings named Rayleigh damping and Localized damping,Selecting models damping ratio according to the damping ratio selection principle,and Introduce two kinds of boundary conditions called static boundary and free field boundary,the model using the two kinds of artificial boundary In FLAC3 D.(2)Adjusting proper the selected seismic waves,According to the structure of the field intensity,Adjusting the peak acceleration on the basis of the acceleration adjustment principle of more severe earthquake,design earthquake and severe earthquake.Using Fortran language program realize to the seismic inversion which then needs filtering and baseline correction making use of SeismoSignal software.(3)Establishing free field model,Doing dynamic response calculation to the free field and analyzing the displacement and acceleration amplification factor,Base on vibration inversion theory,using Fortran language program realize to the seismic inversion,Analyzing to the different seismic inversion results.(4)Reserching the factors affecting the seismic response of subway station,Study factors of different input mode of Seismic wave,different seismic waves,different peak acceleration,different hardness soil layer and the thickness of theoverlying soil etc,that's factors influence to stress,displacement,acceleration under The dynamic response of subway station.It is concluded that under the effect of different seismic wave,the structure of the stress,displacement and acceleration dynamic response is very different;Under different peak acceleration of seismic wave impact,with the increase of peak acceleration,the structure of the stress and displacement is larger,but the acceleration amplification coefficient remain unchanged approximately;With the increases of hardness soil layer,the structure of the stress,displacement and acceleration magnification coefficient decreases;With the increase of the thickness of covering soil,the structure of the stress,displacement and acceleration magnification coefficient is increased also.