跨铁路混凝土箱梁顶推施工过程分析及监测

Construction Process Analysis and Monitoring of Concrete Box Girder of the Overpass Crossing Railway by Incremental Launching Method

结合上跨京广铁路立交桥施工过程,介绍了桥梁顶推施工的计算分析方法。根据结构特点与顶推方案,建立有限元模型,模拟桥梁顶推施工的全过程,详细分析了结构内力、支点反力、截面应力以及导梁变形的变化规律。根据顶推施工过程的分析结果制订了监测方案,并对顶力、顶进速度、中线偏位、桥墩位移、箱梁应力、导梁变形等项目进行了全过程监测。当监测数据发现异常时发出预警信息并及时采取处理措施,保证了顶推施工顺利进行。

Based on the construction process of an overpass crossing Beijing-Guangzhou railway,the calculation and analysis methods of incremental launching construction for overpass are introduced. On the basis of structural characteristics and incremental launching scheme of the overpass,a finite element model is established to simulate incremental launching process of the whole overpass,and variation of force and deformation is analyzed in detail,including the structural internal force,supporting point reaction,section stress and deformation of the guiding girder. According to the analysis results of incremental launching process,monitoring scheme is established,and the jacking force,pushing speed,midline deviation,pier displacement,box girder stress,deformation of the guiding girder and so on are all monitored in the whole process. Early warning information is given when abnormal monitoring data is found,and measures are taken timely to ensure incremental launching construction smoothly.