跨越多层立交大跨径、宽截面钢箱梁整体式顶推施工技术  

Integrated Incremental Launching Construction Technique for Long-Span Broad Cross Section Steel Box Beam across Multilayered Interchange

作　　者：杨庆琪 

机构地区：[1]中铁大桥局集团第七工程有限公司,湖北武汉430056

出　　处：《世界桥梁》2015年第4期20-24,共5页World Bridges

摘　　要：武汉二环线武昌接线梅家山立交主线高架桥第四联为(36.95+62+36.95)m钢箱梁桥,钢箱梁总重达1 800t,标准段桥面宽26.04m。为确保现有交通不被中断,采用节段拼装、整体顶推的方式完成该联钢箱梁的安装。沿顺桥向设置7处临时墩,临时墩采用钢管立柱通过联结系形成整体受力,尽量利用桥墩承台做其基础;钢管立柱顶部设置滑道梁和抄垫支座,滑道梁采用钢箱梁结构,钢箱梁与滑道梁之间设置聚四氟乙烯滑板,以减小顶推摩擦力;导梁设计全长约35m,采取变截面分段设计;横向限位装置安装在墩顶的凹槽上;选用2套自动连续顶推系统进行顶推施工,1套连续千斤顶最大顶推力为500kN,正常顶推速度约10m/h。The viaduct on the main interchange line in Meijiashan is part of the Second Ring Road in Wuhan,the fourth continuous unit of which is designed as a（36.95＋62＋36.95）m steel box beam bridge.The steel box beams have a total weight of 1 800 tand the deck of the typical beam sections is 26.04 mwide.To avoid the interruption to the current transportation system,the steel box beams in this continuous unit were assembled in sections first and were subsequently installed into position by integrated incremental launching.Along the bridge length,seven provisional piers,which were steel pipe posts linked by bracings to bear load integrally,were installed.It is better to use the pier caps as the foundations of the provisional piers.On the top of the steel pipe posts,track beams and template bearings were installed.The track beams are steel box structures,and between the steel box beam and the track beams,PTFE pads were installed to reduce the frictional force generated during the incremental launching.The launching nose,adopting variable cross section and incorporating several sections,is totally about 35 min length.Transverse stoppers were put in the notches on the pier top.Two sets of incremental launching system capable of conducting continuous operation were used in the construction.A set of jack system capable of continuous operation has a maximum pushing force of 500 kN,with a typical pushing speed of about 10m/h.

关 键 词：立交桥 钢箱梁 顶推法 拼装支架 顶推支架 限位结构 线形 桥梁施工 

分 类 号：U445.462[建筑科学—桥梁与隧道工程]