虹桥式木拱桥结构力学特性分析

Analysis of Structural Mechanical Characteristics of Timber Arch Bridge in Style of Rainbow Bridge

虹桥式木拱桥以独特的编木拱结构解决了木结构大尺度无柱跨越的问题,但由于诸多原因,历史上存留下来的古代木拱桥很少,目前对此木拱桥结构性能方面的研究还较为缺乏。为研究其矢跨比、节间数以及拱肋截面尺寸对编木拱结构力学性能的影响规律,以一座虹桥式木拱桥为例,通过改变其矢跨比、节间数以及拱肋截面尺寸的三个参数形式,分别建立有限元模型进行对比分析研究。研究表明,拱肋结构的矢跨比主要通过影响构件节点处的几何关系来影响结构的承载能力;而拱肋结构的节间数和拱肋截面尺寸主要通过影响构件的刚度来影响结构的承载能力的。

The timber arch bridge in style of rainbow solves the problem of large-scale pillarless spanning of wooden structures with a unique braided wooden arch structure. However, due to many reasons, there are few ancient wooden arch bridges left by now. At present, there is still a lack of research on its structural performance. In order to analyze the influence of the rise-to-span ratio, arch section number and the size of the arch rib on the mechanical properties of the wood arch, this paper takes a timber arch bridge in style of rainbow as an example. Finite element models are established for comparative analysis by changing its rise-to-span ratio and arch section numbers. Results show that the rise-to-span ratio of the arch structure mainly affects the bearing capacity of the structure by influencing the geometric relationship at the joint of the member, while the arch section number and the cross-sectional dimensions of arch rib mainly affect the bearing capacity of the structure by affecting the stiffness of the member.