反复荷载下型钢混凝土柱受扭损伤试验研究

Experimental research on torsional damage of steel reinforced concrete columns under cyclic loading

为研究型钢混凝土柱在反复荷载下的受扭损伤,完成了11根型钢混凝土柱和1根钢筋混凝土柱复合受扭试验。通过试验观察了构件的受力过程和破坏特征,研究两种不同型钢混凝土柱的裂缝开展与分布规律。基于能量守恒定律,考察了柱截面配钢形式、扭弯比、轴压比、混凝土强度等级、配箍率以及配钢率对累积损伤的影响。研究结果表明:型钢混凝土柱的损伤演变分为3个阶段:弹性阶段、弹塑性阶段和破坏阶段;配钢形式、扭弯比和配箍率是影响型钢混凝土柱损伤程度的重要因素;配型钢,降低扭弯比和提高配箍率对于损伤指标分别最大降低了22.1%、14.3%和14.0%;损伤指标受轴压比、配钢率和混凝土强度等级影响程度较小。

To study the torsional damage of steel reinforced concrete(SRC)columns under cyclic load,eleven SRC columns and one reinforced concrete column under cyclicloading were tested.The process and patterns of the SRC members were observed,the crack development pattern and the crack distribution were studied in the test.Then the influence of column’s steel form,axial compression ratio,torsion-bending ratio,concrete strength,stirrup ratio and reinforcement ratio on accumulated damage was studied based on the law of energy conservation.The result of analysis is that the damage evolution of SRC columns was divided into three stages.There are elastic stage,elastic-plastic stage and failure stage.The steel form,torsion-bending ratio and stirrup ratio play an important role in the damage accumulation of SRC columns.With adding shape steel,reducing torsion-bending ratio and increasing stirrup ratio respectively decrease the damage index by 22.1%,14.3%and 14.0%.The damage index suffers less impact from axial compression ratio,reinforcement ratio and concrete strength.