钢管混凝土(单圆管)肋拱面内极限承载力计算的等效梁柱法

根据试验研究与双重非线性有限元计算分析结果，提出钢管混凝土（单圆管）肋拱面内极限承载力的等效梁柱法。分析讨论了等效梁柱法的等效长度、作用力选取和钢管混凝土梁柱极限承载力计算方法的选用。分析结果表明，等效梁柱法中钢管混凝土梁柱的极限荷载宜采用DL／T规程；对于非对称荷载。等效长度可取0．72S（S为半跨拱轴线弧长）、采用拱脚截面内力作为作用力；对于对称荷载，等效长度可取0．62S、拱顶截面内力为作用力。与采用双重非线性有限元计算的极限承载力的比较表明，等效梁柱法能基本反映钢管混凝土（单圆管）肋拱极限承载力的基本规律，可供进一步研究与工程应用参考。

Equivalent Beam-column Method for Calculation of the Ultimate Load-carrying Capacity of Concrete Filled Steel Tube(Single) Arch under In-plane Loads

Based on the results from experimental researches and dual nonlinear finite element analyses,the equivalent beam-column method to predict the plane ultimate load-carrying capacity of the CFST(single) rib arch is proposed.The equivalent lengths,applied forces and calculation method of the ultimate load of CFST are analyzed.Analysis results indicate: It is better to calculate the strengths of CFST beams and columns by using Code DL/T;take 0.72S(the arc length of the arch axis)as the equivalent length and the inner forces at the springing section as the acting forces when the arch loads are asymmetrical;take 0.62S(the arch length of the arch axis) as the equivalent length and the inner forces at the crown section as the acting forces when the arch loads are symmetrical.Comparisons with the dual-nonlinearity finite element method show that the predicted results of the equivalent beam-column method follows the basic rule of the ultimate loads of the CFST(single) rib arch and they may be referred to in future research and engineering practice.