大跨连续刚构钢桁梁桥预应力钢混承台施工技术

Construction Technology of Pre-stressed Steel-concrete Bearing Platform for Large Span Continuous Rigid Frame Steel Truss Bridge

云碧峰大桥项为大跨连续刚构钢桁梁桥,下部结构采用预应力钢混承台,预应力钢混承台内置超大承台钢结构。介绍了预应力钢混承台结构形式,并针对承台钢结构加工制作中超厚承压板制孔、拼接难度大,纵横开孔板连接件装配精度要求高,以及承台钢结构吊装易变形、定位难度大等问题,对承压板厚板制作、用于纵横开孔板连接件的组立工装、增加吊装牛腿及型钢支撑架和限位槽钢等施工技术进行总结,并对承台钢结构吊装工况和落位工况进行有限元分析,确保施工技术的可靠性,为类似项目积累了经验。

The Yunbifeng Bridge project is a large span continuous rigid frame steel truss bridge,with a pre-stressed steel-concrete bearing platform for the lower structure.The pre-stressed steel-concrete bearing platform is equipped with a super large steel structure for the bearing platform.The structural form of pre-stressed steel-concrete bearing platform is introduced.In response to the high difficulty of dilling and splicing ultra-thick bearing plates in the processing and production of bearing platform steel structures,the high requirements for assembly accuracy of vertical and horizontal perforated plate connectors,and the high difficulty of deformation and positioning during the hoisting of bearing platform steel structures,construction technologies such as the production of thick bearing plates,assembly fixtures for vertical and horizontal perforated plate connectors,addition of lfting brackets,steel support frames,and limit channel steel are summarized.The finite element analysis is carried out on the hoisting and positioning conditions of the bearing platform steel structure,so as to ensure the reliability of the construction technology and to accumulate experience for similar projects.