配螺旋箍筋方钢管混凝土柱力学性能研究

Study on mechanical performance of spiral stirrup-confined concrete-filled square steel tubular columns

为了研究配螺旋箍筋方钢管混凝土柱的力学性能,在试验基础上应用ABAQUS软件建立了方钢管混凝土柱的有限元模型,对比分析了配螺旋箍筋方钢管混凝土柱与普通方钢管混凝土柱的力学性能,得到螺旋箍筋对混凝土具有约束加强作用的影响规律。在此基础上,进一步对配螺旋箍筋方钢管混凝土柱进行参数化分析,研究了混凝土强度等级、螺旋箍筋间距、螺旋箍筋直径、螺旋箍筋强度等级对配螺旋箍筋方钢管混凝土柱轴压承载力的影响。结果表明:提高混凝土强度等级、减小螺旋箍筋间距和增大直径均能有效提高配螺旋箍筋方钢管混凝土柱的轴压承载力,而改变螺旋箍筋强度等级对提高配螺旋箍筋方钢管混凝土柱的轴压承载力效果不明显;配螺旋箍筋方钢管混凝土柱的轴压承载力与其用钢量近似成正比关系。在相关规范的基础上,推导了适用于配螺旋箍筋方钢管混凝土柱的轴压承载力计算公式,并验证了其合理性。

For investigating the mechanical performance of spiral stirrup-confined concrete-filled square steel tubular columns（ CFTs）,finite element models were established by ABAQUS software based on the tests. Restraint strengthening effect laws of spiral stirrup on concrete were obtained through comparison of spiral stirrup-confined CFTs and general CFTs.Parametric analyses were carried out on spiral stirrup-confined CFTs to study influences of concrete strength,spiral stirrup spacing,spiral stirrup diameter and spiral stirrup strength grade on axial compression capacity. Results show that increase of both concrete strength and stirrup diameter and decrease of stirrup spacing can enhance the axial compression bearing capacity of spiral stirrup-confined CFTs,whereas the increase of stirrup strength grade is helpless. The relation between steel quantity and axial compression bearing capacity of spiral stirrup-confined CFTs is linear basically. Based on relevant codes,the axial compression calculation formulas for spiral stirrup-confined CFTs were deduced and verified.