EXPERIMENTAL STUDY ON SEISMIC AND REPLACEABLE PERFORMANCE OF REPLACEABLE ENERGY DISSIPATION BEAMS WITH BOLTED END PLATES

To study the seismic performance and replaceable capacity of energy dissipation beams with bolted end plates, four replaceable energy dissipation beam specimens were designed and fabricated. The effects of length ratio on seismic performance and replaceable capacity of the replaceable energy dissipation beams were investigated through quasi-static test. The results show that specimens with small length ratio present a shear dominated behavior including web-to-stiffener weld fracture, web buckling and web tear. Whereas the failure features of shear and flexure dominate the behavior of specimens with large length ratio, manifested as flange buckling and end plate-to-flange weld fracture. All tested specimens exhibit stable hysteresis behavior, excellent deformation ability and energy dissipation capacity. In addition, the bearing capacity of replaceable energy dissipation beams is strengthened significantly, and the average value of the overstrength factor is about 1.9. The replaceable energy dissipation beams with bolted end plates can be replaced after the earthquake. Moreover, the energy dissipation beams can be replaced conveniently after the earthquake when the residual angle at the beam end is 0.0020 rad-0.0046 rad. Meanwhile, the main stress development of replaceable beams can be divided into three stages of serviceability, non-essential and mandatory replaceability according to the deformation relationship between the replaceable link beams and the proposed frame structure system.