珠海洪鹤大桥主桥施工关键创新技术  

Key Innovative Technologies in Main Bridge Construction of Honghe Bridge in Zhuhai

作　　者：陈山亭[1] CHEN Shan-ting(The Fifth Engineering Co. ,Ltd. ,China Railway Major Bridge Engineering Group,Jiujiang 332001,China)

机构地区：[1]中铁大桥局集团第五工程有限公司,江西九江332001

出　　处：《桥梁建设》2021年第6期126-131,共6页Bridge Construction

摘　　要：珠海洪鹤大桥主桥由磨刀门水道主航道桥和洪湾水道主航道桥2座斜拉桥串联而成,2座主航道桥均为主跨500 m的双塔双索面结合梁斜拉桥。该桥水中主墩均采用2.8 m钻孔灌注桩群桩基础,主梁采用钢-混结合梁结构。针对钻孔深度深、基岩倾角大且强度高等施工难点,采用了“旋挖钻+回旋钻”的组合成孔技术,充分发挥2种钻机在不同地层的钻进性能优势,具有快速、优质、节能、环保等特点;针对超深多层串珠式溶洞成孔慢的难题,优化成孔钻头的结构形式,并利用反循环冲击钻成孔技术,不仅提高了溶洞成孔工效及成孔质量,而且有效避免了出现卡钻、偏孔等事故;针对主墩临近航道或位于浅滩区,大型船舶无法直接施工的难题,主墩墩顶区钢梁架设采用了无支架法快速架设技术,具有安全风险低、成本投入少等优点。The main bridge of Honghe Bridge in Zhuhai consists of the Modaomen waterway main channel bridge and the Hongwan waterway main channel bridge.The two bridges are arranged in tandem and are all two-pylon steel-concrete composite girder cable-stayed bridges with main spans of 500 m,and the stay cables are fanned out in double cable planes.The piers standing in water are all supported by group pile foundations composed of bored piles of 2.8 m in diameter.The boreholes were deep,and the bedrocks were hard and with large dip angles,which made the boring work quite challenging.The combined rotary drilling and spinning technique was adopted to make good use of the two ways of borehole formation,aiming to accelerate the drilling speed,save energy,minimize disruption to the environment and result in good borehole quality.To facilitate the borehole formation in the region with ultra-deep and multi-layer beaded karst caves,the drilling bits were optimized and the reverse circulation drilling rigs were used to improve the borehole forming efficiency and quality,and avoid the incidents of bit stuck and borehole deviation.The main piers were either near to the navigation channel or located in the shoal area,as a result,large barges could not be employed for construction.The steel girder sections atop main piers were installed by a rapid method without scaffolds,which reduced the construction safety risk and saved the costs.

关 键 词：斜拉桥 钻孔灌注桩 旋挖钻 回旋钻 组合成孔技术 反循环冲击钻 无支架架设钢梁 施工技术 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.4[交通运输工程—道路与铁道工程]