马鞍山长江公铁大桥Z3号桥塔施工关键技术  

Key Construction Techniques of Pylon Z3 of Maanshan Changjiang River Rail-cum-Road Bridge

作　　者：潘博[1,2] 李维 刘爱林 PAN Bo;LI Wei;LIU Ailin(China Railway Major Bridge Engineering Group Co.,Ltd.,Wuhan 430050,China;State Key Laboratory of Bridge Intelligent and Green Construction,Wuhan 430034,China;China Railway Shanghai Group Co.,Ltd.,Shanghai 200071,China)

机构地区：[1]中铁大桥局集团有限公司,湖北武汉430050 [2]桥梁智能与绿色建造全国重点实验室,湖北武汉430034 [3]中国铁路上海局集团有限公司,上海200071

出　　处：《世界桥梁》2024年第2期29-35,共7页World Bridges

基　　金：中国中铁股份有限公司科技研究开发计划项目(2021-专项-03)。

摘　　要：巢马城际铁路马鞍山长江公铁大桥主航道桥为(112+392+2×1120+392+112)m三塔钢桁梁斜拉桥,Z3号桥塔为超高多肢钢-混组合塔,高308 m。上塔柱钢结构高87.5 m,分13个吊装节段,最重505 t;中、下塔柱混凝土结构高217.5 m,分38个节段液压爬模施工;钢-混结合段高3 m,内部采用PBL键+剪力钉+高强度钢锚杆+高强度混凝土结构形式。在中塔柱设置钢管临时横撑控制塔柱线形及应力;下横梁采用落地支架法分层施工,与对应塔柱同步浇筑;钢-混结合段混凝土采用C60细石补偿收缩混凝土+高强度灌浆料,保证了混凝土施工质量;采用工厂“2+1”立体匹配制造、“提升站+运输栈桥”钢塔节段转运等技术,并研制15000 t•m超大型塔吊,实现了钢塔柱大节段的制造、整体滩地运输和吊装;钢塔节段间采用栓焊组合连接形式,通过设置工艺隔板、双面坡口等措施控制了钢塔焊接变形;利用定位桁架临时锁定钢塔合龙段实现了钢塔的精确合龙,定位桁架受力及变形均满足要求。Carrying a section of Chaohu-Maanshan Intercity Railway,the main navigation channel bridge of Maanshan Changjiang River Rail-cum-Road Bridge is a steel truss girder cable-stayed bridge,featuring its three pylons that create two main spans of 1120 m,two side spans of 392 m and two end spans of 112 m.The pylon Z3 is a multi-column,steel-concrete composite structure rising 308 m.The 87.5 m-long steel upper columns contain 13 segments,with the maximum segment weight reaching 505 t.The intermediate and lower pylon columns,measuring 217.5 m high,incorporate 38 segments that were installed by hydraulic climbing formwork.The steel-concrete joint sections are 3 m long,cast by C60 fine aggregate shrinkage compensating concrete and high strength grout,with PBL connectors,shear studs,and high strength steel anchor rods and high-strength concrete for connection.Temporary lateral bracings were installed inside the steel tubes of the intermediate pylon columns for alignment and stress control.The lower pylon crossbeam was cast in layers on ground scaffolds,parallel with the casting of connecting pylon column segments.The pylon segments were match-assembled in a"2+1"manner in the fabrication yard and transferred via lifting stations and transportation trestles.The 15000 t•m-capacity large tower crane was developed to achieve the long-segment fabrication,integral transportation and installation in shoal area.The pylon segments were welded and bolted together,where partitions and double-sided grooves were deployed for welding deformation control.To ensure the accurate closure of the steel pylons,positioning trusses were applied to temporarily lock the key segments.The calculations show that the load bearing performance and deformation of the positioning trusses met the requirements.

关 键 词：斜拉桥 钢-混组合桥塔 超高多肢 钢-混结合段 整体吊装 钢塔合龙 栓焊组合连接 施工技术 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U443.38[交通运输工程—道路与铁道工程] U445.4