自复位圆钢管混凝土柱——钢梁连接节点足尺试验研究

A FULL-SCALE TEST ON SELF-CENTERING CIRCULAR CONCRETE FILLED STEEL TUBULAR COLUMN TO STEEL BEAM CONNECTIONS

为了减小钢管混凝土柱—钢梁框架结构震后的残余变形,提出了一种腹板摩擦式自复位圆钢管混凝土柱—钢梁连接节点型式。介绍了自复位节点的构造,并对其受力性能进行了理论分析。通过3个自复位节点试件的低周反复加载试验,研究节点在循环荷载作用下的自复位和耗能能力。分析了自复位节点可能的破坏模式,钢绞线预应力和摩擦装置螺栓的预紧力对节点受力性能的影响,还分析了钢绞线预应力的变化规律和节点主要部位应变的变化特点。研究结果表明,腹板摩擦式自复位圆钢管混凝土柱—钢梁连接节点具有良好的耗能和自复位能力。节点初始刚度、临界开口弯矩和自复位能力随钢绞线预应力的增大而提高。节点耗能能力随腹板摩擦装置螺栓的预紧力的增大而提高。

To reduce the residual deformation of concrete-filled steel tubular column-steel beam frame structure after earthquakes,a self-centering circular concrete-filled steel tubular column-to-steel beam connection with web friction devices is proposed.The details of the self-centering connection are introduced and its mechanical behavior was theoretically analyzed.The self-centering and energy dissipation capacities were investigated by quasi-static tests on three connection specimens.The possible failure modes of the self-centering connection and the effect of strand prestress force and bolt prestress force of the web friction device on the mechanical performance of the connection were analyzed.The variation of the strand prestress force and the strain in main parts of the connection were also analyzed.The results show that the connection had good self-centering and energy dissipation capacities.The initial stiffness,the imminent gap-opening moment and the self-centering capacity of the connection increased with the increasing of the initial strand prestress force.The energy dissipation capacity of the connection was enhanced with the increasing of the bolt prestress force of the web friction device.