Shaking Table Test And Comparative Analysis Of Seismic Performance Of G/CFRP Reinforced Concrete Frame Structures

The application of FRP(Fiber Reinforced Polymer)bars in concrete structures can solve the problem of steel corrosion,which has become a hot research area in the field of civil engineering.At present,the application research of FRP at home and abroad mainly focuses on structural members,but the study on the overall seismic performance of FRP reinforced concrete frame is less.Because the shaking table test can truly reproduce the seismic process,it is an important means to study the mechanism of structural seismic failure and the most direct method to evaluate the overall seismic behavior of structures.Therefore,the shaking table test of FRP reinforced concrete frame has important scientific significance for the popularization and application of FRP reinforced concrete structures.In this paper,two concrete frame models with CFRP(Carbon Fiber Reinforced Polymer)bars and GFRP(Glass Fiber Reinforced Polymer)bars were made respectively.The overall seismic performance of these two frame structures was studied by shaking table test.According to the analysis and processing of test data,the seismic performance of the two models were compared and analyzed from the aspects of structural dynamic characteristics,acceleration response,displacement response and hysteretic performance.At last,the seismic performance of these two frame structures was analyzed and evaluated by the means of Incremental Dynamic Analysis(IDA).The main research results are as follows:Firstly,two frame models of CFRP bars and GFRP bars with a scale of 1/4 were made.Besides,the similarity relation design,material selection,model making and material performance test were introduced in detail.At the same time,four seismic wave,Taft wave,El-Centro wave,Wenchuan wave and Lanzhou wave were selected to simulate the earthquake action at four different levels(seven degrees of frequent occurrence,seven degrees of fortification,seven degrees of rare occurrence and eight degrees of rare occurrence).Shaking table tests of two models were completed under 30 test conditions.Secondly,from the dynamic characteristics,acceleration response,displacement response and hysteretic performance of the model structures,the overall seismic performance of the two model structures was analyzed and compared.The results show that the inter-story displacement of the concrete frame structures with GFRP bars and CFRP bars is shear-type deformation,which indicates that the lateral displacement of the structure is mainly caused by the bending deformation of beams and columns.The model structure has the largest seismic response to Wenchuan wave.At the same peak acceleration,the maximum acceleration response of the model appears on the top floor of the frame.Comparing the natural vibration period,acceleration response,displacement response and bearing capacity of two models,the seismic response of GFRP reinforced concrete frame was stronger than that of CFRP reinforced concrete frame.Thirdly,the incremental dynamic analysis method was introduced from the basic principle,analysis steps,parameter selection,definition of limit state and processing method of IDA curve.Ground peak acceleration and maximum inter-story displacement were selected as seismic intensity index and structural damage index respectively.The data of shaking table test were analyzed by IDA curve.Besides,the seismic performance of the structure was evaluated from the perspective of probability statistics and seismic fortification level.