Seismic Security Analysis Of Big Segment Passenger Dedicated Railway Big Long Tunnels

With the development of construction in cities and the exploitation of underground space, the abundance different of underground buildings are constructing.However due to the lack of basic information, A perfect method for the seismic design of underground structure was presented still.The seismic design code for subway in our country isn'tyet comprehensive.These make the research about the seismic design of underground structrure more important and urgent.In this paper the summary of worldwide typical instances of tunnels behavior duringearthquake and research developments&methods is briefly described,the characteristics regarding the tunnel damages during earthquake and classification are summed up,the damage mechanism of action from earthquake is described too.Based on the transient dynamic method of ANSYS compute software is used to study the mutual action principles of variety surrounding rock&tunnel lining materials,different geologic conditions and different depth. Results of the analysis reflects that the seismic response of lining construction have the following disciplinarians1. A great deal of earthquake impairments indicate that the buried structure suffered earthquake don't always be safe,so the seismic performance research of buried structure is necessary. Based on the basic theory of soil-structure interaction,a finite element model for the analysis of soil-buried structure dynamic interaction is one of useful way which could greatly improve the efficiency of calculation2. The seismic response of buried lining structure have a great difference between considering two-way coupling earthquake with only considering the level earthquake,the results indicate that the stress and displacement of the lining structure which suffer two-way coupling earthquake is larger than the one-way earthquake.The vertical earthquake will affect the seismic response of lining construction which only suffering the level earthquake. So only taking into account of the level seismic response is not safe to buried structure and it should take into account of the cumulation of two-way earthquake.3. The geologic condition have a great influence to the seismic response which increase with the parameters of geotechnical materials increased.It is because the structural distortions increase and it has nothing with its own inertia and structural rigidity. So the flexibility and tractility of the buried structure should be more thought about which could improve the seimic response of construction performance4. The depth of buried structure have a great influence to its dynamic interaction.In a certain scope,the depth of buried structure is larger,the seimic response is more safe5. In response to the seimic response analysis,the two side walls of underground structure are easier to have a large stress and deformation. So the two side walls and its extremity is the most vulnerable parts.We should take care of it in the design and construction processAt the same time,discuss the lifeblood engineering of structural seismic analysis.A reasonable calculating method and effective scheme of protection is provided.The important meaning of doing one's best at earthquake disaster prevention and seismic for tification of lifeblood engineering was expounded.