大跨径整孔预制箱梁张拉方式及反拱度设置研究  

Study on Tension Mode and Inverted Arch Setting of Whole Hole Precast Box Girder with Large Span

作　　者：姜鸿伟 Jiang Hongwei(The Fifth Engineering Co.,Ltd.of China Railway 13th bureau group,Tianjin 300451,China)

机构地区：[1]中铁十八局集团第五工程有限公司,天津300451

出　　处：《市政技术》2021年第6期56-59,共4页Journal of Municipal Technology

摘　　要：基于有限元分析法和工程实测法,对比研究了大跨径整孔预制箱梁张拉方式对其反拱度设置和后期挠度的影响。选择某案例中构成桥梁主体结构的5×70 m预制箱梁作为研究对象,通过有限元分析法在分次张拉和分批张拉2种张拉方式间进行选择,在混凝土材料力学试验数据和有限元结构力学分析模式下,选择了箱梁的反拱策略,并在反拱策略下对比实测结果进行了效果分析。研究结果表明,分批张拉方式的积累挠度优于分次张拉方式,应力储备在安全区间范围内;选择的张拉方式和反拱度设置方法相配合,在大跨径整孔预制箱梁施工过程中,具有工程指导意义。The influence of the tension mode of the whole hole precast box girder with long-span on its inverted arch setting and later deflection was comparatively studied.The 5×70 m precast box girder,the main structure of the bridge,was selected as the research object.Through the finite element engineering mechanics analysis method,the box girder was selected between two methods such as tension in stage and in batches.Under the experimental data of concrete material mechanics and the finite element structural mechanics analysis mode,the inverted arch strategy was selected and the effect was analyzed.The results showed that:the long-term cumulative deflection performance of the batch tensioning mode was better than that of the stage tensioning mode.The stress reserve was within the safe range.The selected tension mode matched the inverted arch setting mode.It had practical significance in the construction process of the whole hole precast box girder with large-span.

关 键 词：大跨径 整孔预制箱梁 张拉方式 反拱度设置 

分 类 号：U448.35[建筑科学—桥梁与隧道工程]