L形冷弯钢管混凝土柱轴压受力性能研究

Study on mechanical properties of L-shaped concrete-filled cold-formed steel tubular column

为研究L形冷弯钢管混凝土柱在轴心受压荷载作用下的受力性能和承载力计算方法,建立L形钢管混凝土柱轴压有限元模型,并将有限元分析结果与文献中的试验结果进行对比,二者吻合较好。通过对L形冷弯钢管混凝土短柱进行有限元模拟,分析了L形冷弯钢管组合形式、钢管壁厚、材料参数、柱肢长宽比以及钢管成型工艺对其轴压承载力的影响。研究表明:冷弯型钢应用于L形钢管混凝土柱时,可利用其角部冷弯效应及倒角特性约束内部混凝土,有效提高柱轴压承载力;L形钢管成型工艺和钢管壁厚、柱肢长宽比对承载力提升有一定影响;当柱肢的长宽比为2.5左右时,钢管对混凝土的约束效率最高;屠永清等提出的承载力计算方法与有限元分析结果较为符合。

To study the mechanical properties and calculation methods of the bearing capacity of L-shaped cold-formed concrete-filled steel tubular column under axial compression load,a finite element model for the simulation study was established and the simulation results were proved in good agreement with experimental results reported in literatures.Through finite element simulation of L-shaped cold-formed concrete-filled steel tube columns,the influence of Lshaped cold-formed steel tube combination form,forming process,material parameters,and length-to-width ratio of column flange on the strength of stub columns was analyzed.Research has shown that when cold-formed steel is applied to L-shaped steel tube concrete columns,its corner cold bending effect and chamfering characteristics can be used to constrain the internal concrete,effectively improving the axial compressive bearing capacity of the columns.The forming process of L-shaped steel pipes,the wall thickness of steel tube and the length-width ratio of column limb have a certain impact on the bearing capacity.When the length-to-width ratio of the column flange is about 2.5,the steel pipe has the best restraining effect on concrete.The bearing capacity calculation method proposed by Tu Yongqing is in good agreement with the finite element analysis results.