Analysis Of RC Frame Structure Collapse And Residual Displacement Based On IDA Method

In the event of an earthquake,collapsing damage occurs if the deformation of the RC frame structure reaches the collapse limit.In recent years,there are many criteria for failure of reinforced concrete frame structure,but how to choose the collapse judgment criterion in practical application is not conclusive,and the collapse of the building is the main cause of casualties and property damage.Therefore,it is very important to establish a more accurate collapse failure criterion for the RC frame structure.Based on this,this paper introduces the incremental dynamic analysis method,and deeply studies the collapse of reinforced concrete frame structure under earthquake action.The main work and conclusions are as follows:(1)Summarize the failure criterion of RC frame structure at home and abroad and draw down six fall failure criteria,which are based on strength,deformation,energy,deformation and energy double parameter,stiffness and IDA method failure criteria.Select the IDA method based on the deformation and failure criteria for collapsing contrast analysis.(2)Before the incremental dynamic analysis,taking into account the influence of the platform segment of the selected seismic record response spectrum and the excellent period Ts of the site,10 seismic waves were selected according to the two frequency bands of the response spectrum,and the SeismoSingnal ground motion analysis software Determine Sa(T1,5%),and finally use hunt & fill unequal step amplitude modulation of its amplitude.A 10-layer three-span RC frame analysis model was established by using SAP2000 finite element software and a series of elasto-plastic time-history analysis was carried out.The obtained IM and DM were connected into IDA curve and collapsed by "half-taking" Status point.(3)to calculate the amplitude coefficient corresponding to the state point of building collapse,the seismic record of the amplitude modulated and again the elastoplastic time history analysis;find out the interlayer displacement angle reaches the deformation limit 1/50 and the last moment hinge diagram and then in the analysis process,were analyzed and summarized the situation of hinges beam column: deformation collapse failure criteria underestimate the collapse-resistant capacity risk and IDA criterion are lower than the deformation criteria based on damage evaluation of structure(4)defines the concept of the residual interlayer displacement angle and uses it as a structural damage index in IDA analysis.By comparing the structural damage index with the IDA collapse analysis of the interlayer displacement angle,the latter is more effective than the former,and the former is more sensitive to the former.(5)IDA by using different structural damage index of structure vulnerability analysis and vulnerability curve comparison found in DM IDA analysis,DM for residual interlayer displacement angle IDA analysis of the vulnerability curve obtained under the earthquake to assess the risk of collapse is conservative,suitable for some of the more important structure.