Study on seismic performance of beam-end flange reinforced joints of concrete-filled centrifugal precast concrete column-steel beam

In the joint of centrifugal precast concrete column and steel beam (RCS), stress concentration at the joint of flange and through partition commonly occurs due to the variable cross-section, and the weld between cylinder and beam end is prone to brittle fracture under earthquake action. To mitigate this issue, pseudo-static tests of three full-size joints with different structures of beam end flanges were designed and conducted in this paper. The influence of different beam end strengthening forms on the seismic performance of the joints was studied. The results show that beam hinge failure occurs at all joints. The joint hysteresis curves are full and the energy dissipation capacity is good. Compared with the normal RCS joint, the displacement ductility coefficient and bearing capacity of the joints with side plate widening and arc expansion are increased by 14. 95%, 35. 51%, 30. 79% and 31. 48% respectively. The ductility and bearing capacity of the joint can be effectively improved by the side plate widening and arc expansion. The arc expansion method can alleviate the stress concentration at the transition section and avoid premature joint failure and can better enhance the bearing capacity and seismic performance of the joints compared to the side plate widening method. Therefore, it is recommended for use in the RCS frame system in high intensity earthquake areas. © 2024 Science Press. All rights reserved.