长细比对五螺箍矩形RC柱轴心受压承载力影响

Influence of slenderness on axial compressive bearing capacity of 5-spirals rectangular RC column

五螺箍作为一种新型的组合式螺旋箍筋,它的主要特色之一是可以将螺旋箍筋推广应用于矩形断面的钢筋混凝土柱。本文采用ABAQUS先对已有试验结果进行有限元模型验证,然后建立具有初始偏心的不同长细比的构件进行轴心受压加载破坏过程的有限元分析,并通过有限元分析结果得出的长细比与稳定系数定量关系,拟合出五螺箍矩形RC柱稳定系数计算公式。结果表明:相同截面下,随长细比增大,五螺箍构件轴压承载力随长细比增加而降低较小,五螺箍矩形RC柱当长细比由2增加到12时,其承载力降低分别为5.5%、4.6%、3.5%,通过计算结果拟合出其稳定系数计算公式,并在计算分析的基础上提出五螺箍矩形RC柱稳定系数取值建议。

As a new type of combined spiral stirrups,one of the main features of 5-spirals is that it can be applied to rectangular reinforced concrete column.Firstly,we perform FEA model verification on existing test results through ABAQUS, and then set up with finite element models which have an initial eccentricity,and apply axial comprssion loading on different slenderness ratio of the component under axial compression loading,and through the finite element analysis results of slenderness ratio and stability coefficient of the quantitative relationship between fitting out five spiral hoop stability coefficient calculation formula of rectangular RC column.The results show that under the same section,the axial compression bearing capacity of 5-spirals decreases slightly with the increase of ratio of length to fineness.When the slenderness ratio increases from 2 to 12, the bearing capacity decreases by 5.5%, 4.6% and 3.5%, respectively. On the basis of calculation and analysis, the stability coefficient of the RC column with 5-spirals is suggested.