Experimental Research On Beam-column Joint Reinforced With CFRP

CFRP has been used in the field of reinforcement widely because of its high tensile strength and modulus of elasticity, light weight, corrosion risistance and simple construction. CFRP has been used to reinforce many concrete members domestic and oversea, in which mass are girders, boards and columns, seldom is beam-column joints. Though the known and ripe reinforced technique has been used in reinforcement for beam-column joints, there has no preferable method can solve the question of reinforcement for joints, because its construct is complex and destroy form is multiform. Therefore we must study the part farther.The experiment adopts CFRP to reinforce the end of beam-column joints, and studies the bearing capacity of 2 reinforced joints under dead load and the aseismic behaviour of 4 under low-cycle reversed load .The dead-load experiment studies the reinforcing effect of 4 anchore methods, including bearing capacity, cracks development, bending defection change, and reinforcement strain. The experiment indicates that cracking load would be enhanced when the close CFRP hoop was set at the end of beam, and the bearing capacity would be enhanced when adopt angle iron in the corner, however many cracks would be appear here. If there is close CFRP hoop at the end of beam while adopt angle iron in the corner, the bearing capacity would be enhanced greatly, simultaneously cracks development would be controlled. The experiment also indicates that reinforced members have biggish rigidity, lesser bending defection, lesser ductility, and lesser reinforcement strain. Such is evident when there are both close CFRP hoop at the end of beam and angle iron or close CFRP hoop in the corner.The paper mainly studies their aseismic behaviour under low-cycle reversed load. There paper consideres two influencing factors: concrete intensity and anchor methods. The reinforced members' cracking load, bending load and destructive load are improved. The close CFRP hoop on the beam can restrict concrete, so as to enhance its bearing capacity and stay cracks happenning and development. The paper studies reinforced-members' hysteresis loop, stiffness digration, energy dissipation, ductility, reinforcement strain and shearing deformation of core of beam-columnjoints. The reinforced members have plump hysteretic loops, lesser stiffness degration, higher energy dissipation and hingher ductility factor. Because the exist of CFRP, reinforcement strain can be controlled. The experiment shows that the corner must be anchored well when fabric's end is anchored on column, and the close CFRP hoop on the beam's plastic zone makes the best use of CFRP on beam bottom.