方钢管高强混凝土偏压构件的试验研究与理论分析

本文进行了8根方形截面钢管高强混凝土单向压弯构件的试验研究,研究构件在不同长细比、偏心率和含钢率下的力学性能,长细比取25.4、50.8和71.6三种,偏心率在0.140～0.288之间变化,含钢率取8.2%和14.3%两种。研究结果表明:构件的承载力随着长细比和偏心率的增加迅速降低,含钢率为8.2%的构件在达到极限承载力之前钢管出现了局部屈曲。在进行试验研究的同时,还编制了非线性分析程序BC,用来分析方钢管高强混凝土压弯构件的力学性能,理论分析结果和试验结果进行了对比,两者吻合较好,在此基础上分析了长细比、含钢率、混凝土强度和钢材屈服强度等因素对偏压构件N/Nu(η)-M/Mu(ζ)相关曲线的影响。

Experimental research and theoretical analysis of high strength concrete filled square hollow section steel tubes subjected to eccentric loading

This paper presents an experimental research of 8 high strength concrete filled square hollow section (SHS) steel tubes subjected to eccentric loading. The primary parameters of the specimens were slenderness ratios(25.4, 50.8 and 71.6), eccentricity ratios (from 0.140 to 0.288), and steel ratios (8.2% and 14.3%). The experimental results showed that the bearing capacity decreased rapidly with the increase of the slenderness ratio and eccentricity ratio. The local buckling of the steel tubes was observed for the specimen whose steel ratio uses to be 8.2%. At the same time, a nonlinear analysis program BC was developed to calculate the load deflection curves at the mid height of eccentrically loaded columns. The numerical results were compared with the experimental results, and they agreed well with each other. Then based on the program, the influence of parameters, such as slenderness ratio, steel ratio, concrete strength and steel yield strength on the interaction curve N/Nu(η) M/Mu(ζ) was discussed.