Research on seismic performance of new prestressed precast beam-column sleeve concrete frame joints

In this paper, a new type of prestressed precast beam-column sleeve concrete frame joint was proposed, and the seismic performance of such joints was investigated through cyclic load tests. The beam-column connections of the joint were wrapped with steel sleeve to reduce the concrete pressure loss to some extent. The method of assembling precast beams and columns with prestressed steel strands and high-strength bolts can make the joints have good ductility and easy to be replaced after the earthquake. Five precast reinforced concrete joints with different parameters and one cast-in-place reinforced concrete joint were tested under cyclic load. The influence of the thickness of stiffening rib of beam steel sleeve, the magnitude of effective prestress and the setting of side plate of column steel sleeve on the seismic performance of this type of joint were studied. The research results showed that the design of this type of joint meet the concept of strong columns and weak beams, and strong joints and weak components. And this type of joint had better seismic performance than cast-in-place components. The thickness of stiffening rib of beam steel sleeve and initial prestress had significant influence on the bearing capacity and seismic performance of the specimens. The produced plastic hinges had better energy dissipation capacity than that of steel sleeve, but the steel sleeve was easy to be replaced after the earthquake.