The Seismic Behavior Of The External Beam-Column Joints Of R.C Frames Strengthened By Carbon Fiber

Reinforced concrete beam-column joints are important elements in the frame structures. They connect the beam and column, transverse and distribute the inertial forces. They also coordinate the structure's deformation; ensure the integrity of the structure. Once joints are destroyed, the consequence will be very serious. So it is necessary to do some research on strengthening the frame beam-column space joints.Currently, some experiments have done on the intermediate joints Strengthened by CFRP, but most of these were regarding plane joints, and yet space joints were rarely involved. This paper will continue to study the external beam-column joints of intermediate floors of R.C Frames, and focus on seismic performance of joints after reinforcement. By the experiment and nonlinear finite element analysis, the force mechanism and reasonable reinforcement method of space joints strengthened by CFRP are revealed.In this paper, there are five external joints of intermediate floors of R.C Frames were designed with the different reinforcement parameters strengthened by CFRP. One of them was not strengthened by CFRP; the remaining four specimens were strengthened by CFRP in different methods. In this paper, the numerical simulation of five external beam-column joins are used which is under a monotonic load, to observe the process from cracking to damage of the five specimens. By the comparison of numerical results between the control and strengthened specimens in aspect of damage mode, ultimate load, stiffness and other fields, to find the best seismic reinforcement method of space joints.