新型 Y 形主梁大跨度桥梁方案设计研究

Study on Scheme Design of New Y-shaped Girder Long-span Bridge

摘要:

Y形主梁一般应用于小跨径人行桥，但实际工程中，有时也需要建设主梁呈Y形、主梁各分支交点处无条件设置桥墩的大跨度车行桥。为了适应上述条件要求，一种由“撑杆-主梁”组合受力的新型Y形主梁大跨度桥梁结构体系被提出。通过分析该结构体系的传力机制，介绍了采用该结构的某桥梁工程的设计方案和受力情况。同时，采用有限元软件分析并总结了该结构体系随主梁水平夹角变化的内力和反力变化规律，为类似建设条件下的桥梁设计提供了有益参考。

Abstract:

Y-shaped girder is generally used for small-span pedestrian bridges. But in practical projects, it is sometimes necessary to build a long-span vehicular bridge with Y-shaped girder and unconditional piers at the intersection of each branch of the main girder. In order to meet the requirements of the above conditions, a new type of new Y-shaped girder long-span bridge structure system with combined forces of "strut and girder" is proposed. By analyzing the force transmission mechanism of the structure system, the design scheme and stress situation of a bridge project with this structure are introduced. At the same time, the finite element program is used to analyze and summarize the internal force and reaction change law of the structural system with the change of the horizontal angle of the girder, which provides a useful reference for bridge design under similar construction conditions.