Seismic Research Of Civil Air Defense Underground Structure

Civil air defense engineering is an important component of national defense construction.It plays an important role in wartime and peacetime.But the civil air defense underground structure is not safe enough to avoid being destroyed under the earthquake load in practice.Thereby,it will be pay more attention to researching on the earthquake resistance abilities and measures.In this project,we study on the earthquake damage mechanism of civil air defense engineerings based on the investigating the earthquake damage of many underground structures.Through the method of two-dimensional and three-dimensional dynamic numerical simulation of underground civil air defence structure by using ANSYS and FLAC3D program,we find the influence of seismic failure modes,failure mechanism,structural parameters of structures,medium conditions and seismic waves.Based on the structural dynamic response analysis,We find that the middle column is the most vulnerable area with concentrated force and large deformation of of slab structures of civil air defense engineerings,as same as the corner of the wall.The ground floor vibration response of the multi story underground structure is the largest,and the acceleration,maximum stress,maximum strain and relative displacement are all larger than the top layer.At the same time,according to the analysis and comparison of the different working conditions,the influence of the structural parameters,geological conditions and seismic waves on the seismic response of the structure is obtained.