蝴蝶拱空间受力特点及承载能力研究

Study on Space Stress Characteristic and Carrying Capacity of Butterfly Arch

该文以一座实际蝴蝶钢拱桥为对象,通过建立全桥三维有限元模型,应用弹塑性和几何非线性计算方法,分析了全桥的应力和变形,并通过对变形最大的小拱肋拱顶截面的变形分析,研究了异型拱肋的稳定特性。结果表明拱肋的局部失稳对结构整体极限承载能力不取控制作用。同时比较了大拱肋和吊杆的应力和变形随荷载系数的变化的特征,数据显示吊杆的刚度对结构的承载能力有较大的影响。

Taking a practical butterfly steel arch bridge as an example,the article analyzes the stress and deformation of the whole bridge by setting up the three-dimensional finite element model and applying the elastic-plastic and geometric nonlinearity calculation method.According to the analysis on the maximum deformed section at the arch top of small arch rib,the article the stability characteristic of the special-shaped arch rib.The result shows that the partial unstability of arch rib will not play the control role for the limit carrying capacity of the whole structure.By the comparison of the stresses of the large arch rib and the suspender,and the character of deformation with the variation of loading coefficient,the data show that the rigidity of suspender will more greatly influence the carrying capacity of structure.