内置格构式圆钢管的T形型钢混凝土柱力学性能试验研究

EXPERIMENTAL RESEARCH ON MECHANICAL BEHAVIOR OF LATTICED CIRCULAR TUBES REINFORCED CONCRETE T-SHAPED COLUMNS

异形柱结构较传统框架结构能有效地改善建筑内部的使用空间,但目前应用较多的钢筋混凝土异形柱存在高轴压比下抗震性能不足,对水平荷载的方向性非常敏感等问题,其房屋高度和抗震设防烈度受到严格限制,制约了其在高设防烈度地区进一步的推广和应用。型钢混凝土异形柱相对于钢筋混凝土异形柱,其抗震性能有所改善,为此,该文提出了内部设置格构式圆钢管的T形型钢混凝土柱。进行了格构式型钢混凝土柱轴压、偏压和压弯滞回性能的三组系列试验,研究了上述试件的破坏模式与力学性能,分析了格构式型钢骨架的作用机理和对混凝土破坏模式的影响。试验结果表明,内部格构式型钢骨架能够保持整体工作,同时限制了型钢混凝土的粘结滑移,一定程度上延缓了混凝土的破坏。相对于钢筋混凝土试件,在轴压和偏压荷载工况下,型钢混凝土的承载力和延性显著提高;在压弯滞回荷载工况下,型钢混凝土的承载力和耗能性能得到改善。

Special-shaped column structures might improve residential architectural space effectively, compared with traditional frame structures. However, the widespread special-shaped reinforced concrete （RC） columns present insufficient aseismic behavior with a high axial load ratio and sensitivity to the horizontal loading direction, and have strict limitations in aseismic behaviors, in respect to applicable building height and aseismic fortification intensity, which hampers further generalization and application of special-shaped columns in a high aseismic fortification zone. Special-shaped steel reinforced concrete （SRC） columns behave advantages on the aseismic behaviors over special-shaped RC columns. A kind of T-shaped steel reinforced concrete column with latticed steel tubes in the sectional branch components is introduced. Three series of experimental investigations on the axial, eccentric and hysteretic properties of the columns were conducted. Failure modes and mechanical properties of the specimens were investigated, and the mechanisms of the latticed steel tubes and their improvement for concrete failure mode were also studied. Experimental results reveal that： the tube skeleton bears load as integrity, restricts the bond-slip between the concrete and latticed tubes, and postpones the concrete damage to a certain extent. Compared with the RC columns, the SRC columns present enhancement in resistanceand ductility under axial or eccentric loads, and improvement in resistance and energy dissipation capacity under hysteretic loads.