The Earthquake Response Analysis Of Reconstructed Underground Structure With Soil-structure Interaction

In recent years,the scale of construction and development of underground structures has continued to expand,and its seismic safety performance has been paid more and more attention.At present,the seismic design of the above-ground structure has been extensively studied.The seismic research of the underground structure started later than the above-ground structure,and its seismic response still needs further study.The seismic response of the above-ground structure and the underground structure is very different.The seismic response of the above-ground structure is mainly due to its own inertial effect,while the seismic response of the underground structure is mainly due to the constraint of the soil body.Generated by interaction.Reconstructed underground structures also belong to the category of underground structures.Due to the connected above-ground parts,their seismic response characteristics are for further study.In this paper,based on the previous research results,a finite element software ANSYS was used to establish a frame structure containing a basement to simulate a reconstructed underground structure.Considering the soil-structure dynamic interaction,a three-dimensional dynamic response analysis under earthquake action was performed on it.To study the seismic dynamic response of reconstructed underground structures,the main contents are as follows:1.This paper summarizes the research of the background of the underground structures,research status and research methods of earthquake resistance of underground structures,and introduces the numerical calculation method of soil-structure dynamic action adopted in this paper to study the seismic response of underground structures.2.It briefly introduces the theoretical basis required for the overall finite element analysis method of soil-structure interaction using the finite element software ANSYS,including the establishment and solution of dynamic equations,the constitutive relationship of soil and materials,and the damping equations of soil and materials.,Numerical simulation of artificial boundaries in infinite domain,dynamic contact relationship between soil and structure,selection of seismic motion and equivalent input.3.The program implementation method and specific process of viscoelastic artificial boundary and equivalent input of ground motion are introduced.Based on the near-field wave finite element method,the viscoelastic artificial boundary conditions and the equivalent input of ground motion are realized.A three-dimensional surface source problem is used as an example The effectiveness of the viscoelastic artificial boundary was verified,and a free-field seismic response example was used to verify the correctness of the equivalent input program of ground motion.The free-field dynamic response analysis of the site soil was conducted to analyze the seismic response characteristics of the site soil under different ground motion.4.Based on the theoretical basis and procedures of the previous chapters,the soil-structure dynamic interaction model is established,and the seismic response analysis of the structure is carried out through the seismic response of different cross sections of the structure.The influence of different ground motion input characteristics on the seismic response of the structure is analyzed.From the analysis,it is known that the peak value of the ground motion has a significant effect on the seismic response of the underground structure.The effect of the structural spectrum characteristics on the seismic response of the underground structure can be matched by the average frequency of the fourier spectrum intensity.Better response.The influence of structural elastic modulus,structural density and soil elastic modulus on the seismic response of the structure is analyzed.