非对称配钢钢骨混凝土柱抗震性能试验研究

为研究非对称配钢钢骨混凝土柱的抗震性能，进行了12个T形配钢、12个L形配钢的钢骨混凝土柱试件在低周往复荷载作用下的试验研究，试验参数为剪跨比、轴压比、体积配箍率以及是否配置拉结筋，对受力过程、破坏形态、滞回特性、骨架曲线、延性、耗能能力等进行了分析比较。结果表明，在恒定轴向荷载和水平低周往复荷载共同作用下，非对称配钢钢骨混凝土柱表现出较好的受力性能，破坏形态主要有弯曲破坏、剪切黏结破坏、剪切斜压破坏、剪切复合型破坏4种，各试件表现出较明显的正负滞回环不对称现象。剪跨比对破坏形态有较大影响，剪切复合型破坏主要发生在配有严重不对称的L形配钢的试件中；各试件的延性性能均随轴压比的增大而降低，在L形配钢试件中更为明显；增大配箍率对T形配钢试件的延性和承载力均有明显的提高，并能改善试件屈服后的耗能能力，有效改善混凝土的脆性性质，但对于剪跨比较小的L形配钢试件受力性能的改善并不明显；配置拉结筋能够提高各试件的承载能力，改善加载后期试件的承载力衰减和刚度退化，并明显增强了L形配钢试件的变形能力。

Experimental study on seismic behavior of steel reinforced concrete column with unsymmetrical steel cross-sections

To study the seismic behavior of unsymmetrical steel reinforced concrete column, cyclic loading tests were carried out on 12 columns with T-shaped section steel and 12 columns with L-shaped section steel. The test parameters included shear span ratio, axial compression ratio, stirrup ratio and presence of cross tie. Mechanical process, failure mode, hysteretic characteristics, skeleton curves, ductility and energy dissipation ability were taken into comparison. The result indicates that unsymmetrical steel reinforced concrete column possesses good seismic performance under constant axial compression and cyclic horizontal load. The failure modes include bonding failure, shear-bond failure, shear compression failure and shear-composition failure. Obvious asymmetry phenomenon of positive and negative hysteresis loop are shown. The span ratio has great influence on failure mode and shear-composition failure usually takes place in L-shaped steel section column. With the increase of axial compression ratio, the ductility decreases, which is obvious in L-shaped steel section column. The ductility and bearing capacity of the T-shaped steel section columns are improved greatly with the increase of stirrup ratio, but not obvious for T-shaped steel section column with smaller span ratio. Cross ties can improve bearing capacity, limit strength and stiffness degradation and enhance deformation capacity of L-shape steel section columns clearly.