Research On Seismic Behavior And Bearing Capacity Of RC Beam-column Joints With High-strength Stirrups

In recent years, high-strength concrete is being applied increasingly widely. Usinghigh-strength stirrups to confine high-strength concrete can overcome the brittleness ofhigh-strength concrete, improve its strength and ductility, make the seismicperformance of structure better, meanwhile, the shear capacity of reinforced concretemembers can also be enhanced and the consumption of reinforcement could be reduced.Therefore, researching on high strength concrete confined with high strength stirrups isof great significance.RC beam-column joint, as an important part of framework structure, is not onlythe force transmission hub but also the weakness of the framework. In this thesis, byusing means of experimental study, theory analysis and numerical simulation,reinforced concrete frame node confined with high-strength stirrups will beinvestigated deeply, the main research contents as fellows： pseudo-static experimentson5RC beam-column joints with high-strength stirrups are carried on，the influencesof high-strength stirrups on the seismic performance of joints are evaluated, theinfluences of the type of stirrups, stirrup ratio to shear bearing capacity, ductility andenergy dissipation capacity are considered too. Basing on modified compression fieldtheory, the shear-carrying capacity analytic model of beam-column joints is established.Analyzing the shear-carrying capacity of86experimental specimens national andinternational and experimental specimens in this article; considering the influences ofconcrete strength, axial compression ratio, stirrups ratio and stirrup strength;contrasting theory results with experimental results; the reliability of the shear-carrying capacity analytic model is verified. Basing on OpenSees structure nonlinear analysisplatform, the finite element analysis model of RC beam-column joints confined withhigh-strength stirrups is established. Using this model to simulate the nonlinearanalysis of specimen in this paper, comparing the simulation results and test results，thereliability of the finite element analysis model is validated.