采用泰勒级数作为分段插值函数,在考虑多个截面的平衡条件和紧箍效应钢管混凝土应力-应变关系、剪切变形及初弯曲影响的基础上,建立杆件截面的平衡方程,提出四肢缀条轴压钢管混凝土格构柱弹塑性极限承载力数值方法,并编制相应的计算程序。利用提出的计算方法和编制的程序对国内已有轴压四肢钢管混凝土格构柱试件进行计算,并与现有一些规程进行比较。同时,结合数值计算结果及长细比折减系数计算模型,提出长细比折减系数计算公式。利用提出的长细比折减系数计算公式对国内已有轴压四肢钢管混凝土格构柱试件进行计算,并与数值计算结果及试验结果进行比较。研究结果表明:该方法适用于轴压长柱和短柱的弹塑性极限承载力的计算。规程计算方法结果偏于保守,计算误差大,本文方法的计算结果与试验结果较吻合;本文提出的长细比折减系数计算公式正确。
Based on the equilibrium condition of several sections,the stress?strain relationship of the concrete-filled steel tube under the effect of confinement and the influence of the initial bending and shear,the equilibrium equation of the section was established.At the same time,the numerical method for calculating the elastic-plastic ultimate loads of the concrete-filled tubular laced columns was presented by adopting the Taylor's series as the piecewise interpolation function and the corresponding computer program was compiled.Some axial compressed four-tube concrete-filled steel tubular laced columns were computed using the numerical method and the program,and the results were compared with the calculation results of some existing codes.The calculation formula of slender ratio reduced coefficient was proposed combining numerical calculation results and the slender ratio reduced coefficient model.The calculation results were compared with the numerical calculation results and the test results.The results show that this method is suitable for the elastoplasticity ultimate bearing capacity calculation of the long and short axial compressed columns.The code computational methods are conservative,the computational errors are great,and the computed results in this article agree well with the test results.The rationality of slender ratio reduced coefficient calculation formula has been attested.