山区公路曲线拱桥合理悬臂长度计算

为了研究山区公路曲线拱桥设计方法，以跨径120m、桥面平曲线半径400m、拱肋轮廓曲线半径900m的曲线拱桥为研究对象，根据桥面各种受力工况及桥梁本身的受力情况，通过整桥有限元模型分析，研究拱脚、1／4拱肋和拱顶处扭剪应力与桥面悬臂长度的变化关系，从而获得合理的桥面悬臂长度；同时通过对其他跨径进行有限元分析计算，得到不同跨径、不同平曲线半径桥面合理的悬臂长度，并给出了不同跨径、不同平曲线半径下桥面悬臂长度的计算公式。提出的设计方法可为曲线拱桥的设计提供参考。

Calculation of Rational Cantilever Length on Mountain Highway Curve Arch Bridge

In order to analyze the design methods of mountain highway curve arch bridge, a curve arch bridge was studied, in which the span diameter was 120 m, the curve radius of the deck outline was 400 m, and the outline curve radius of the arch rib was 900 m. By the analysis of finite element model for the whole bridge, the relations between the torsional shear stress and the bridge cantilever length, at the arch foot, 1/4 arch rib and vault, were studied and the rational deck cantilever length was obtained. Through finite element analysis of other curve arch bridges with different spans, the optimum values of the deck cantilever with different spans, different horizontal curve radius decks were obtained, and the calculation formulae of the deck cantilever length were given. The design method proposed in the paper can provide reference for curve arch bridge design.