大跨度钢箱梁步履式顶推施工控制研究

Research on Walking-type Incremental Launching Construction Control for Large-span Steel Box Girders

大跨度钢箱梁步履式顶推施工控制是确保施工过程中结构安全,成桥线形和应力符合设计要求的关键。本文以官溪河大桥主桥为工程背景,对大跨度钢箱梁步履式顶推施工控制进行研究。采用有限元仿真分析方法对全桥施工过程进行分析,研究顶推施工过程中主梁线形和应力的变化规律,确定各梁段施工预拱度。制定现场施工监控方案并开展施工中线形和应力实时监测,通过对理论值与实测值对比分析,表明施工过程中全桥线形和应力控制良好,施工过程结构安全。

The control of walking-type incremental launching construction for large-span steel box girder is the key to ensuring structural safety during the construction process,and safeguarding that the bridge alignment and stress meet the design requirements.This article takes the main bridge of Guanxihe Bridge as the engineering background,and studies the control of walking-type incremental launching construction for large-span steel box girders.The finite element simulation analysis method is used to analyze the construction process of the entire bridge,so as to study the changes in the main beam shape and stress during the jacking construction process,and determine the pre camber of each beam segment during construction.The on-site construction monitoring plans are developed,and real-time monitoring of the alignment and stress during construction is conducted.By comparing and analyzing theoretical and measured values,it is shown that the overall bridge alignment and stress control are good,as well as the structure is safe during the construction process.