SEISMIC PERFORMANCE OF CONCRETE-FILLED STEEL TUBE DEVICES FOR PRECAST CONCRETE BEAM-COLUMN CONNECTIONS

摘要

We develop a novel replaceable energy dissipative device for precast concrete beam-column connections. The device comprises two short concrete-filled steel tubes and a web with a opening. To better understand the seismic behavior of the device, four test specimens were subjected to a cyclic load and one specimen subjected to a monotonic load. The load-carrying capacity, stiffness, hysteretic behavior, energy dissipation capacity and ductility of the device were recorded. The test results indicate that the device has excellent plastic deformation capacity, energy dissipation capacity and ductility. A parametric study was then carried out using finite element analysis, which showed that the index $l_{2}^{3}/EI$ can be used to characterize the bending deformation mechanical properties of the device; usually, a larger value of $l_{2}^{3}/EI$ means that the device has better deformation and ductility capacity. Finally, a numerical simulation analysis of a precast concrete beam-column joint connected by the device proved that the seismic performance of the precast joint can be significantly improved in terms of the deformation capacity, energy dissipation and ductility, while the damage severity of the beam and column members is significantly reduced.