初应力对钢管混凝土叠合柱轴压性能影响

Effect of preload on the axial capacity of CFST reinforced concrete columns

为分析作用于钢管混凝土上的初应力对叠合柱轴压性能影响,该文对受初应力作用的叠合柱进行了有限元模拟。结合有限元模型,分析了不同截面尺寸、钢材及混凝土强度等参数下,初应力对叠合柱轴压承载力的影响规律。结果表明:初应力使得叠合柱荷载—变形曲线后移,轴力集中于钢管混凝土,轴压承载力上升;初应力系数和钢管内外混凝土强度比对其承载力影响显著。在参数分析的基础上,提出了以初应力系数、内外混凝土强度比、约束效应系数为参数,考虑组合作用的初应力叠合短柱极限承载力计算公式。

The effect of the preload on the axial capacity of a CFST encased concrete column was modeled using a finite element model.The influence of the preload on the axial strength of the column was analyzed for various factors such as the section size,steel strength and concrete strength.The results show that the load versus deformation curve for the column with a preload move back with a slight increase in the axial strength.The preload ratio and the ratio of the outer concrete strength to the inner concrete strength significant affect the axial strength.Formulas are given to calculate the axial strength with a preload that considers the influence of these parameters as well as the confinement effect.