Study On Seismic Response Of Prestressed Portal Frame

With the rapid development of China's economy,enterprises from all over the world set up factories in China as a new type of structural system,the prestressed portal frame structure system is highly sought after by the market,the construction area is growing at an extremely fast rate every year.Of at the time of the earthquake disasters and secondary disasters often brings great threat to people's life and property safety,and our country because of its special geographical environment often encountered earthquake hazards,if we can clearly understand the dynamic response of the structure under seismic loading and seismic performance,then we could protect the structure more specifically.This article takes the typical prestressed portal frame structure as the research object,based on seismic theory and finite element dynamic analysis,uses the numerical simulation method,uses the SAP2000 finite element software to establish the simulation model of prestressed portal frame structure,the seismic behavior of prestressed portal frame under different spans has been studied.The main tasks are as follows:(1)The origin and characteristics of prestressed portal frame are summarized.Through the seismic performance and static performance,the domestic and foreign research status of the traditional gantry frame and the new prestressed portal frame are discussed,then through the analysis of several major earthquakes in China,the purpose and significance of this study are clarified.(2)Finite element software SAP2000 is used to conduct modal analysis of prestressed portal frame,and the modal characteristics of the structure are obtained through the analysis,which provides a theoretical basis for the analysis in the following part.(3)PUSHOVER analysis based on static elastoplastic analysis theory,through finite element software SAP2000 to execute numerical simulation,the dynamic response,performance points and plastic hinge distribution of the structure are analyzed,through these analyses,it provides a reference for verifying the seismic performance of the structure.(4)Based on the transient dynamic analysis of seismic waves,using finite element software SAP2000 to establish three-span pre-stressed portal frame simulation model of 24m,30m and 36m,dynamic time history analysis method is used to calculate the dynamic response of structural models under different spans.Comparative analysis of displacement and acceieration response of the overall structure,the influence of span and prestress on the seismic capacity of portal frame structures has been researched,it's provide reference for seismic work of building structures.