Study On Mechanical Behavior And Shear Capacity Of SRC Beam-column Spacial Joints

The beam-column spacial joint as force transmission hub in frame structure of steel reinforced concrete(SRC).It is a reliable security system security framework premise.Under the action of earthquake,the SRC spacial joint will bear the action of axial force,bending moment and shear force from the crossed beam,and the complex force state and spacial coupling effect is generated in the joint.Under this background,the seismic performance and shear capacity of SRC beam-column spacial joint is studied through the combination of numerical simulation and theoretical analysis in this paper.The main research work and results are as follows:1)Analysis and verification of finite element model of SRC beam-column joint.Based on the experimental study of five SRC beam-column joints,the finite element models were established by ABAQUS software and the calculation was compared with test results.The agreement between calculation and test results shows that the simulation model is effective.2)Study on seismic behavior of SRC spacial joint in plane loading path.Based on verification of finite element model of SRC plane joint,the corresponding finite element model of spacial interior joints were established to study the influence of plane loading path to mechanical property.In addition,the effect of slab width,concrete strength grade,steel web thickness and axial compression radio on mechanical property of joints were analyzed.The research shows compared with plane joint,spacial interior and edge joints show a better carrying capacity and dissipation capacity,while the energy dissipation capacity is relatively poor spacial angle nodes.3)Hysteretic behavior and damage evaluation of SRC spacial interior joints underdifferent loading paths.The effect of different loading paths on the hysteretic behavior of spacial interior joints is studied by selecting four spatial loading paths.The carrying capacity and dissipation capacity of joints decreases due to a bidirectional coupling effect in the joints which space loading paths lead to.It also causes stiffness degradation and damage development of joints to accelerate.4)Study on shear capacity of SRC beam-column spacial interior joints.Based on the results of numerical simulation,the force process and load transmission mechanism of SRC spacial interior joints are analyzed.And the calculation method of the shear capacity of the joints is determined.Based on this,the calculation formula of shear capacity of SRC spacial interior joints is proposed.The applicability of the proposed formula is verified by the comparison of the calculated and simulated values.