Simulation Analyses Of Seismic Strengthening Or RC Beam-column Joints Reinforced By FRP And Haunches At Beam Ends

The beam-column joint is the hinge of force transferring for reinforced concrete (RC)frames. It plays the role of connecting beams and columns, coordinating deformation ofcomponents and ensuring the integrity of structures. As joint failure is an important factor tocause collapse of the whole structure and there exists many RC frames with poor aseismaticperformance in China, the study of anti-seismic reinforcing method for joints is verysignificant.As fibre reinforced plastics (FRP), which is a kind of new material, has such advantages ashigh strength and convenient construction, it is superior to reinforce beam-column joints withFRP. At present, the studies of FRP reinforcing method are mainly concentrated oncomponents, while there is less research on the FRP reinforced RC beam-column joints.Numerical analytical method is an effective complement to experimental studies andtheoretical analysis. It can simulate microscopic stresses and strains which can not beobserved easily during test and the results have a certain reliability.Through using finite element analysis software ANSYS,3finite element models for FRPreinforced RC beam-column joints and1finite element model for comparison specimen areestablished in this paper. With the concentrated load acting on the beam end, the mechanicalperformance of the joints is simulated and the failure mechanism and failure mode are studied.In addition, through changing the FRP bond layers and the length of haunches,40other finiteelement models for FRP reinforced RC beam-column joints are established and the influencecharacteristics of each parameter are analyzed. The results indicate that: the shearing capacityof FRP reinforced RC beam-column joints increases with the growth of the FRP bond layerswithin a certain range. When they go out of the scope, the enhancement extent will be smaller,even be zero. FRP bond layers have a certain impact on the ductility of components. Theposition of FRP and the length of haunches have significant influence on the reinforcementeffect.