关键词: 钢管混凝土, 边节点, 梁贯通式节点, 抗震性能

Abstract:

The low-cycle reversed loading experiments of four specimens were conducted to investigate the seismic behavior of the exterior through-beam joint between concrete-filled steel tubular (CFST) columns and reinforced concrete beams. Experimental results show that (1) as the relative reinforcement ratio ( the reinforcement ratio of ring beam / the reinforcement ratio of frame beam) and the relative radio width ratio ( the width of ring beam / the diameter of steel tube) decrease, the plastic hinge transfers from the frame beam to the ring beam, and three failure modes occur, which includes the failure at the frame beam root, the failure at the connection of the frame beam and the ring beam and the failure in the ring beam; (2) the internal force at the roots of the beams can be reliably transmitted to the joint, and the joint can work coordinately with the frame beam and the CFST column; and (3) for the specimens designed on the basis of the principle of“Strong Joint”, the plastic hinge appears at the frame beam root with plump hysteretic curves, relatively large ductility coefficient, concave and convergent stiffness curves and excellent energy dissipation ability, which means that the seismic behavior is good. Therefore, the exterior through-beam joint obtained through reasonable design is safe and reliable under stress, and it can realize the anti-seismic design principle of“Strong Column with Weak Beam is, Stronger in Joints”.

Key words: concrete-filled steel tubular, exterior joint, through-beam joint, seismic behavior