南昌市洪都大道高架桥节段梁结构设计

Structural Design of Segment Girder of Hongdu Avenue Viaduct in Nanchang City

洪都大道高架桥为在国内城市桥梁中首次全面采用预制节段拼装箱梁技术。设计提出标准等宽段采用墩梁固结、体外束为主预应力体系的大悬挑横梁双箱节段梁结构,变宽段采用支座体系、“分箱室、变挑臂”变宽度节段梁结构,是根据城市桥梁特点提出的新型节段梁结构,均属国内首次。对节段梁结构设计、超高渐变段设计、设计标准化、全寿命周期设计等设计要点,以及节段梁工厂化预制、快速化施工工艺进行研究并提出相应对策,达到桥梁造型美观、受力合理、经济环保、施工便捷的目的,在计划工期内顺利建成通车,取得良好的经济效益和社会效益。

For the first time,the prefabricated segment box girder assembly technology is adopted for Hongdu Avenue Viaduct in the urban bridges of China.In the proposed design standard,the equal-width section adopts the large cantilever beam with double-box segment taking pier-beam consolidation and external beam as the main prestressing system,and the variable-width section adopts the girder of support system,"separated box cell,variable cantilever"variable-width segment,which are the new segment girder structures and firstly used in China according to the urban bridge characteristics.This paper studies the design of segment girder structure,design of ultrahigh transition section,design of standardization,design of life cycle,factory-like prefabrication of segment girder and rapid construction technology and puts forward the relevant countermeasures in order to reach the purpose of bridge attractive appearance,stress reasonableness,economic environmental protection and construction convenience.The project is smoothly completed for traffic in the planned construction period,and the good economic benefit and social benefit are achieved.