土压平衡盾构斜切大直径主筋桩群施工技术  

Earth Pressure Balance Shield Construction Technique for Angled Cutting of Large-Diameter Reinforced Pile Groups

作　　者：杨志勇 余俊 刘杰 孙恒 YANG Zhiyong;YU Jun;LIU Jie;SUN Heng(CCCC Second Harbour Engineering Co.,Ltd.,Wuhan 430040;Research and Development Center of Intelligent Manufacturing Technology for Transportation Infrastructure,Wuhan 430040;Key Laboratory of Large-span Bridge Construction Technology,Ministry of Communications,Wuhan 430040)

机构地区：[1]中交第二航务工程局有限公司,武汉430040 [2]交通运输行业交通基础设施智能制造技术研发中心,武汉430040 [3]长大桥梁建设施工技术交通行业重点实验室,武汉430040

出　　处：《都市快轨交通》2024年第1期127-134,共8页Urban Rapid Rail Transit

基　　金：中交第二航务工程局有限公司立项课题(JSKF-20190610-907)。

摘　　要：针对盾构直接切削大直径主筋桩群的工程难题,以广州地铁12号线官洲站—大学城北站区间工程为例,开展盾构直接切削桩径1 200mm、主筋直径25 mm和28 mm桩群的实践研究,分析盾构施工关键措施、切桩效果。实践表明:滚刀和撕裂刀搭配的刀具配置具备切削主筋直径25 mm和28 mm混凝土桩基的能力;镶齿滚刀难以直接切断钢筋,撕裂刀二次作用时对钢筋的剪切作用力可将滚刀切口位置切断;采用“低推速、高转速、稳扭矩”方式掘进可有效切断桩体及钢筋;采用分体式液压钢筋剪可较好处理盾构仓内缠绕钢筋。This study examines shield direct cutting techniques on large-diameter piles within the construction project linking Guanzhou Station to University Town North Station on the Guangzhou Metro Line 12.Focusing on piles with diameters of 1,200 mm and reinforcing bars with diameters of 25 mm and 28 mm,the research evaluates the efficacy of critical measures and the resultant quality of pile cutting within shield construction.Findings indicate that a cutter head configuration,incorporating a hob and a tearing knife,successfully penetrates concrete pile foundations containing rebar of the specified diameters.However,a challenge arises when a toothed hob attempts to sever the reinforcing bar directly.It is observed that the tearing knife’s secondary action exerts adequate shear force to dissect the reinforcement at the pre-cut location by the hob.Furthermore,employing a boring strategy characterized by a low advancement rate,high rotation speed,and consistent torque has proven to enhance the cutting process for both the pile body and its embedded steel bars.Additionally,the use of split hydraulic rebar shears delivers an improved response to the complications presented by intertwined steel bars within the shield machine’s path.

关 键 词：城市轨道交通 盾构 地铁车站 切除桩基 滚刀 大直径钢筋 

分 类 号：U231[交通运输工程—道路与铁道工程]