| Reinforced concrete frame structure is one of the most popular structures in the world,whose seismic behavior is analyzed by many countries.Many earthquakes showed that the joint of reinforced concrete frame was weak part which connected the beams and columns transferring the internal forces.It ensures frame structures’ bearing capacity and rigidity.This article proposed that 600 MPa steel and high-toughness concrete were applied to beam-column joint.The seismic behavior of joint which was reinforced by high-toughness concrete was analyzed to promote the use of 600 MPa steel and high-toughness concrete.Four interior joints with high-strength reinforcement and high-toughness concrete were designed.Under low cycle loading,mechanical analysis target such as failure character,stirrup strain of joint core,concrete strain of joint core,shear distortion and seismic behavior indexes which included bearing capacity,deformability,hysteretic characteristics,stiffness degradation and energy dissipation capacity were analyzed.The results show that high-toughness reinforcement is an effective measure to decrease crack width and concrete shedding area.It can also improve failure patterns,bearing capacity deformation behavior and hysteric characteristics.Furthermore,high-toughness reinforcement can also delay the stiffness degradation,improve energy-dissipating capacity and lighten the degree of cumulated damage.The best rage of high-toughness concrete is from core area of joint to the one time adjacent height of beam to improve failure patterns,deformability,and stiffness degradation.Based on experimental research,ABAQUS was used to build a model.The nonlinear numerical simulation of failure patterns,bearing capacity deformation,hysteresis curve and skeleton curve was calculated.The result shows that finite element simulation results are basically consistent with experimental results. |
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