大跨度连续梁悬臂灌筑施工线形监控技术研究

蒙华铁路跨京广铁路特大桥中大跨度预应力混凝土连续梁采用单箱单室、变高度、变截面直腹板,施工工序和施工阶段较多。为确保梁体能够按设计及规范要求顺利合龙,文章利用有限元正装分析法进行模拟计算,计算出在各种外界因素影响下的梁体预拱度设置,然后通过实测数据与理论数据进行比较分析,对计算模型进行修正。通过施工线形监控、及时发现、及时调整,解决合龙前悬臂端竖向挠度的偏差,使得主梁轴线的横向位移不超过容许值,确保合龙后的梁体线形良好。

Research on Linear Monitoring Technology of Long-span Continuous Beam Cantilevered Construction

The long span prestressed concrete continuous beam of Meng Hua railway across Jing Guang railway of adopts single I>ox single room,straight webs with variable height and variable cross-section,and there are many construction procedures and stages.In order to ensure the beam body can successfully closed,according to the design and specification requirements,in this paper,the jjrecamber setting of beam under the influence of various external factors is calculated by using finite element method,and then by comparing analyzing the measured data and theoretical data,the calculation model is modified.Through the construction linear monitoring,timely detection,timely adjustment,the deviation of the vertical deflection of the cantilever end before closure is solved,the transverse displacement of the main beam axis does not exceed the allowable value,the good alignment of the beam body after closure ensured.