Analysis Of High-rise Building Superstructure-Pile-soil Mass Interaction Under Eearthquake

In order to avoid the damage of the building during the earthquake,the seismic design of building must be done.At present,both Design Code for Foundation of Buildings and Seismic Design Code of Buildings are based on conventional design methods,ignoring the influence of foundation soil and foundations on the superstructure.However,a large number of experimental data and theoretical analysis show that there are interactions between superstructure,foundation and foundation soil under earthquake.The results show that the stress and deformation in practical engineering of the structure under the earthquake action are different from those calculated by the conventional design method.From an economic point of view,material may be wasted on some components,as far as security is concerned,it may cause structural damage.Therefore,it is one of the hot research topics in the field of civil engineering to study the dynamic interaction analysis of the superstructure-pile-soil system under earthquake.This paper uses ansys software to establish a series of frame-shear structure models,And the finite element analysis is carried out.Through the analysis and comparison,the insufficiency of the seismic design of the structure according to the existing building seismic design standard is pointed out,and some reference suggestions are put forward for the internal fore and deformation of structure in practical engineering.The paper has carried out the research on the following aspects:This paper systematically summarizes the research results of analysis models and calculation methods for several commonly used superstructures-pile-foundation soil interactions at home and abroad.The relevant parameters,unit types,connection between different units,and the determination of structural damping and the principle of selection and adjustment of seismic waves applicable to this model are determined.In this paper,through elastic time history analysis of the structure under multiple earthquake actions and the modal analysis,comparing the variation of dynamic characteristics and dynamic response of the structure,When consider the interaction and assume that the bottom is completely fixed.And the changes of the modal analysis results and the dynamic response analysis results of the superstructure when changing the pile diameter and foundation soil stiffness are discussed.The analysis results show that,to considered the interaction,in comparison with the conventional design method,it is considered to chang,which the vibration characteristics,displacement,speed,acceleration and internal force of the superstructure,especially the change of the internal force of the structure can not be ignored.If the size of the pile diameter is appropriately increased within a certain range,the natural vibration period of the structural system changes,and it has a certain influence on the deformation and force of the superstructure.With the change of the stiffness of the foundation soil,the period of natural vibration of the structural system and its seismic response all changed.