T型、N型圆管相贯节点滞回性能实验

对T型、N型圆管平面相贯节点进行循环加载的拟静力实验,以研究两种节点的抗震性能,对象为单个足尺寸的相贯节点。在支管循环加载的过程中对主管施加固定轴向荷载。在主管壁产生局部屈曲后,背向加载支管一侧的主管壁上产生了斜向条纹。节点最终的破坏是主管只管交界处的焊缝根部的裂纹发展直至断裂。实验得到节点滞回特性曲线。能量分析表明,T型节点在受压半周的耗能能力与受拉半周相近,N型节点受压半周的耗能能力强于受拉半周。2个实验节点在循环荷载作用下均具有良好的塑性变形能力。

Hysteretic behavior of T and N joints

Two full-scale tubular T and N joints were tested under cyclic quasi-static loadings to understand their performance under seismic loading.A constant load was applied on the axial direction of the chord during cyclic loading.In the tests,local buckling was observed at the chord in the intersection area.Stripes were found on the chord surface.Crack propagation between the chord and the brace led to the final failure of two joints.The energy analysis indicated that more energy dissipated in the N joint during the compressive half of the cycles than in the tensional half.For T joint specimens,energy dissipation was almost equal during the two halves of the cycles.The hysteretic behavior curves also revealed that the specimens had adequate ductility under cyclic loading.