【摘要】 为研究四肢桁式钢管混凝土(CFST)悬链线拱面内稳定性，采用有限元法开展桁式CFST悬链线拱在轴压或压弯作用下的面内弹塑性屈曲分析。基于试验数据与数值模拟验证模型参数，探讨平面内屈曲破坏模式，揭示屈曲机理；引入全拱和弦杆的归一化长细比，考虑弦杆屈曲影响的交互因数，得到轴压作用下的统一屈曲曲线；提出压弯作用下面内稳定承载力的交互作用方程。结果表明：斜腹管屈曲大幅降低稳定承载力；桁式CFST悬链线拱在屈曲破坏过程中总是存在弦杆变形，弦杆变形对稳定性的影响不可忽视；屈曲曲线可用于轴压桁式悬链线拱，交互方程可为一般荷载作用下的桁式悬链线拱提供较好的下限预测。该结果对四肢桁式CFST悬链线拱的面内稳定性设计具有指导意义。更多还原

【Abstract】 In order to investigate the in-plane stability of quadri-trussed concrete-filled steel tubular(CFST)catenary arches,the elastic-plastic buckling analysis of CFST catenary arches under axial compression or combined compression and bending moment were carried out by finite element method.Firstly,the finite element model parameters were verified based on available test data and numerical simulation.Then the buckling failure mode of trussed CFST catenary arches was discussed,and the buckling mechanism of trussed catenary arches was revealed.Secondly,the unified buckling curve of the trussed catenary arch under axial compression load was obtained by introducing the normalized slenderness ratio of the entire arch chord tube and considering the interaction coefficient of the buckling effect of the chord tube.Finally,an interaction equation of stable carrying capacity on trussed catenary arch under the combined action of pressure and bending moment was proposed.The results show that the buckling of inclined tube greatly reduces the stable carrying capacity on trussed catenary arches,which should be prevented in the design.The chord tube deformation always exists in the buckling failure process of the trussed catenary arch,and the effect of chord tube deformation on its stability should not be ignored.The buckling curve can be used for trussed catenary arches under axial compression load,and the interaction equation can be used to predict the appropriate lower bound of trussed catenary arch under general load.The results have a guiding significance for the in-plane stability design of quadritrussed CFST catenary arches.更多还原