The Comparison Research On The Seismic Performance Of Reinforced Concrete Frame And Concrete Filled Steel Tube Frame

Concrete Filled Steel Tube(CFST)is a structural form that combines the advanta ges of steel structure and reinfo rced concrete(RC)structure.It can not onl y ma ke up for the shortcomings of both steel and concrete materials,but also give full play to their advanta ges.At present,CFST structures are widely used in ma ny fields of civil engineering.The CFST column a nd the RC column are used in the fra me structure.However,there is little co mparison research on the seismic performance of the two structures.It has always been studied for some specific case.It is difficult to co mpare and analyze the seismic perfor mance of RC frame and CFST fra me with ma ny different para meters.In view of those proble m,elasto-plastic ti me history analysis and static elasto-plastic analysis methods have been used to co mpare the shear force,displaceme nt and story drifts of the two fra mes under multiple and rare earthq uake.Influe ncing factors include the number of floors,inte nsity,live load and span.The following results have been obtained from research:(1)24 RC frames and 24 CFST frames have been designed that meet the engineering require ments,and ma ny FEM model are established in ETABS.Through the fitti ng of test results,those model have been validated.The results from modal analysis and spectral analysis show that the CFST frame has s maller bending stiffness and base shear than the RC frame,and has larger period and vertex displacement.(2)Elastic and elastoplastic time history analysis have been performed on all frames.Comparing the shear force of the two fra mes with different parameters,the base shear force and base shear coefficient of CFST frame with different para meters under multiple and rare earthqua ke are smaller tha n those of RC frame.Because CFST column has smaller cross-section and lighter weight than the RC column.(3)The static elastoplastic analysis has been performed on the two frames.By analyzing and co mparing the displaceme nt,story drifts,plastic hinge distribution and developme nt,performa nce and dema nd relation of those structure under multiple and rare earthq uake,the CFST fra me stiffness is found to be smaller tha n that of the RC frame.Both the vertex displacement and the max story drifts are larger tha n the RC frame.(4)Considering the performance and demand relation and the economic factor of the two fra me,the seis mic perfor mance of RC frame and CFST frame has different advanta ges with different parameters.In 1/3 cases,the overall perfor mance of CFST frame is better.In 1/3 cases,the overall performa nce of RC frame is better,and in other 1/3 cases,the overall performances of the two frame are close.