千米级公铁两用悬索桥施工贯通测量与工程精度控制技术

Construction Penetration Survey and Engineering Precision Control Technology of the Kilometer-level Suspension Bridge for Highway and Railway

新建连云港至镇江铁路五峰山长江特大桥主桥主跨1092m,是世界上首座重载、高速、千米级大跨度公铁两用钢桁梁悬索桥。对于千米级大跨度跨越长江的公铁两用悬索桥,架梁工序前贯通测量较常规桥梁无论是技术难度还是精度要求,都更具有挑战性。为确保施工测量精度,保证成桥线路平、纵断面符合设计要求,满足轨道铺设要求,对千米级公铁两用悬索桥施工贯通测量与工程精度控制技术进行研究。介绍了五峰山长江特大桥主桥架梁工序前,施工贯通测量及工程精度控制技术:平面贯通控制测量先按铁路GPS二等精度进行主桥控制点复测和加密控制点统一测量、整体平差,再通过三等附合导线复核加密控制点;高程贯通控制测量按二等水准测量精度采用附合水准路线形式进行,地表测段用电子水准仪观测,墩顶测段采用测距三角高程测量,跨越长江测段采用测距三角高程测量执行二等跨河水准测量,数据采用水准平差软件平差;阐述了以贯通测量成果为基准,进行跨距贯通测量和桥梁竣工测量的方法。通过分析平面与高程贯通控制测量、跨距贯通和桥梁竣工测量数据,成果均符合规范精度要求,实现对工程精度的精确控制,为成桥线路和桥梁构筑物贯通质量和后阶段施工奠定了基础。

The main span of the newly-built Wufengshan Yangtze River Grand Bridge on the Lianyungang-Zhenjiang Railway is 1092m.It is the world’s first heavy-duty,high-speed,kilometer-level large-span steel truss suspension bridge for highway and railway.For the large-span suspension bridge crossing the Yangtze River at the kilometer level,the penetration survey before the girder erection process is more challenging than the conventional bridge in terms of technical difficulty and accuracy requirements.In order to ensure the accuracy of construction survey,ensure that the plan and vertical sections of the completed bridge line meet the design and the requirements of track laying,the construction penetration survey and engineering accuracy control technology of the kilometer-level suspension bridge for highway and railway are studied.This paper introduces the construction penetration survey and engineering precision control technology before the girder erection process of the main bridge of Wufengshan Yangtze River Bridge.The plan penetration control survey shall first carry out the resurvey of the main bridge control points and the unified survey and overall adjustment of the densified control points according to the second-class accuracy of the railway GPS,and then recheck the densified control points through the third-class attached traverse.The elevation penetration control survey is carried out according to the second-class leveling accuracy in the form of the attached leveling route.The surface survey section is observed by the electronic level,the pier top survey section is measured by the ranging trigonometric leveling,and the Yangtze River crossing section is measured by the ranging trigonometric leveling to carry out the second-class river crossing leveling,and the data is adjusted by the leveling adjustment software.The method of span penetration survey and bridge completion survey based on the penetration survey results is introduced.Through the analysis of the plan and elevation penetration control survey,span penetration and bridge completion survey data,the results are in line with the specification accuracy requirements,achieving accurate control of the engineering accuracy,and laying a foundation for the completion quality of the bridge lines,bridge structures and the subsequent construction.