基于壁板屈曲后强度的矩形钢管混凝土偏压承载力计算方法

Calculation Method of Eccentric Bearing Capacity of RCFST Based on Post-buckling Strength of Panels

为了准确计算大宽厚比矩形钢管混凝土短柱偏压承载力,通过有限元方法对非均匀受压单侧约束平板的屈曲性能进行了研究,给出了该类板件的弹性屈曲系数计算公式。以此为基础,结合有效宽度法,提出了基于壁板屈曲后强度的矩形钢管混凝土偏压承载力计算方法。为验证所提计算方法的准确性,建立了大宽厚比钢管混凝土短柱偏压试验数据库,并将该计算方法与各规范的计算方法进行了对比。结果表明:提出的两种大宽厚比矩形钢管混凝土偏压承载力计算方法具有较高的计算精度,计算结果与试验结果吻合良好,其中方法二能够准确地评估构件的偏压承载力,可用于大宽厚比矩形钢管混凝土短柱偏压承载力计算中。

In order to accurately calculate the eccentric compress strength of rectangular concrete-filled steel tube(RCFST) short columns with large width-to-thickness ratio, the buckling performance of non-uniformly compressed unilaterally restrained plates was studied by the finite element method, and the calculation formula of the elastic buckling coefficient of this type of plate was given. Based on this, combined with the effective width method, a calculation method of eccentric bearing capacity of RCFST based on post-buckling strength of panels was proposed. In order to verify the accuracy of the calculation method, the test database of RCFST short columns with large width-to-thickness ratio was established, and the new calculation method was compared with the calculation methods of various codes. The results show that the two proposed methods for calculating the eccentric bearing capacity of RCFST with large width-to-thickness ratio have high calculation accuracy, and the calculation results are in good agreement with the test results. The second method can accurately evaluate the eccentric bearing capacity of components, and can be used in the calculation of eccentric bearing capacity of RCFST short columns with large width-to-thickness ratio.