乐清湾跨海大桥超高变截面节段预制箱梁施工技术

Construction Technology of Precast Super-high Variable Cross-section Box Segments for Yueqingwan Sea-crossing Bridge

乐清湾跨海大桥1号桥主跨上部结构为预应力混凝土连续刚构,人字坡桥面、超高、变截面、腹板不等高、节段预制的单箱单室双幅箱梁,下部结构主墩墩身采用V形墩。结合该桥特殊设计与整体施工工期要求,节段箱梁采用工厂化、短线匹配法预制,并对节段梁预制台座布置、模板配置与设计、钢筋绑扎、混凝土浇筑与养护等主要施工环节进行分析,优化施工方案。

The upper structure of the main span of the No.1 bridge of the Yueqingwan Sea-crossing Bridge is a continuous rigid frame of prestressed concrete. The upper structure is a single-box single-chamber double-span box girder with a herringbone slope bridge deck,super-high,variable section,unequal web height,and segment prefabrication. The main piers of the substructure adopt V-shaped piers. Combining the special design of the bridge with the requirements of the overall construction period,the box girder of the segment is prefabricated by the factory and short-term matching method. This paper analyzes the main construction links of segmented beam precast pedestal layout,formwork configuration and design,steel bar lashing,concrete placement and maintenance,and optimizes the construction scheme.