| As an important part of the building structure,beam-column joints are the hubs of structural transmission and internal force distribution,and their destruction will lead to the collapse of the whole building structure.In order to make the structure meet the seismic design principle of "strong column and weak beam" in the ductile frame,the section size is often too large or stirrup configuration is too large,which brings great trouble to the construction,and it is difficult to effectively control the cracks.Steel fiber reinforced concrete（SFRC）,as a new type of green material,has the characteristics of high strength,good ductility,and strong energy dissipation capacity.Research shows that the application of SFRC in buildings can significantly improve the ductility and energy dissipation capacity of structures.To study the seismic performance of SFRC beamcolumn joints under earthquake load,based on the existing experimental research,this paper uses the nonlinear analysis software ABAQUS to carry out numerical simulation and theoretical analysis of SFRC beam-column joints.The main research contents are as follows:（1）The finite element software ABAQUS was used to establish the model of SFRC beam-column joints,and the simulation results were compared with the experimental failure state,hysteretic curve,skeleton curve,damage,and energy dissipation capacity.The results showed that the established model had high accuracy and can be used to simulate the seismic performance of SFRC beam-column joints.（2）On the basis of verifying the accuracy of the finite element model,20 beamcolumn joint models were designed respectively,and the influences of concrete strength,steel fiber volume ratio,axial compression ratio,and stirrup ratio in the core area on the seismic performance of SFRC beam-column joints were further analyzed.The results showed that increasing the concrete strength had little effect on the peak load of SFRC beam-column joints,but the ductility of the specimens increased first and then decreased gradually.Increasing the volume ratio of steel fiber and the stirrup ratio in the core area of the joints can effectively improve the seismic performance of SFRC beam-column joints.Increasing the axial compression ratio can increase the peak load of SFRC beamcolumn joints in a certain range.When the axial compression ratio was less than 0.3,the peak load increases with the increase of the axial compression ratio.However,when the axial compression ratio is greater than 0.3,the peak load decreased with the increase of the axial compression ratio.（3）According to the equilibrium equation,the deformation compatibility equation and the constitutive relation,a new method for calculating the shear capacity of the core area of steel fiber reinforced concrete beam-column joints is established.Through the experimental verification of 20 steel fiber reinforced concrete beam-column joints,the results show that the theoretical calculation value is close to the experimental value,and the dispersion is good,which can effectively calculate the shear capacity of steel fiber reinforced concrete beam-column joints. |
PDF Full Text Request