钢管混凝土核心柱轴压极限承载力

Bearing capacity of axially compressed core columns having concrete-filled steel tubes

为了研究钢管混凝土核心柱的轴压性能及轴压极限承载能力,以钢管混凝土核心柱中钢管混凝土及矩形箍筋约束混凝土的应力应变关系为基础,结合已有的试验及理论研究成果,将钢管混凝土核心柱轴压破坏过程分为3个阶段,定义了钢管混凝土核心柱的轴压极限状态,并提出了钢管混凝土核心柱轴压极限承载力的计算公式。该计算公式明确反映了箍筋套箍指标对核心柱承载能力的影响。计算结果与试验吻合良好。

The behavior and bearing capacity of core columns with concrete filled steel tube under axial compression were studied. The axial compression failure process was divided into three parts based on the concrete stress-strain relationship of the concrete-filled steel tube and the concrete confined by the rectangular transverse reinforcement. The limiting compression state was identified with a new method developed to predict the axial compression bearing capacity of core columns. In most core columns used in engineering projects, the outer concrete confined by the rectangular transverse reinforcement reaches its peak strain before the inner concrete confined by the steel tube. The core column failure then begins with the outer concrete＇s failing. Therefore, the analysis considers the effect of the confinement index on the transverse reinforcement. The predicted values agree well with the test results.