武汉杨泗港长江大桥超大型锚碇施工关键技术  

Key Construction Techniques for Massive Anchor Block of Yangsigang Changjiang River Bridge in Wuhan

作　　者：韩胜利[1] HAN Sheng-li(The First Engineering Co.,Ltd.,China Railway Major Bridge Engineering Group,Zhengzhou 450053,China)

机构地区：[1]中铁大桥局集团第一工程有限公司,河南郑州450053

出　　处：《世界桥梁》2020年第4期30-34,共5页World Bridges

摘　　要：武汉杨泗港长江大桥为主跨1 700m的单跨双层悬索桥,武昌侧锚碇为重力式锚碇(由地下连续墙、帽梁、内衬、底板及填芯混凝土组成),锚碇开挖直径98m、深39m,位于长江大堤南岸附近,地质条件较差。根据锚碇结构特点和地质条件,地下连续墙共划分68个槽段,Ⅰ、Ⅱ期槽段各34个,间隔分布,分别采用成槽机和铣槽机施工,接头形式为铣接头;基坑开挖前,采用地下连续墙墙底注浆、接缝处旋喷、抽水井等止排水措施,深基坑开挖采取逆作法施工,边开挖取土方边施工内衬,采用履带吊机将土方从基坑内吊出,帽梁和内衬分8段施工;锚碇底板、填芯大体积混凝土分层分块施工,采用冷却循环水、低水泥掺量的混凝土配合比等温控措施,保障了锚碇施工质量。The Yangsigang Changjiang River Bridge in Wuhan is a single-span suspension bridge with span length of 1 700 m.The bridge has two layers of highway decks.The Wuchangside anchor block is a gravity anchor block comprising diaphragm walls,cap beams,linings,base slabs and cavity-filling concrete.The pit excavated for the anchor block measured 98 min diameter and 39 min depth,near to the south embankment of Changjiang River where the geological condition is poor.The diaphragm wall was divided into 68 trench sections according to the structural characteristics of the anchor block and geological condition,with equal amount of 34 sections in the phasesⅠandⅡ.The phaseⅠand phaseⅡtrench sections were alternately distributed,constructed by using the trench excavation and milling machines,and the ends of adjacent trench sections were milled to joint.Before the foundation pit excavation,the base of the diaphragm wall was grouted,the joints were jet grouted and pumping well was built,aiming to contain water.The deep foundation pit was excavated by a top-down method,with the soil excavation and lining placement carried out in parallel.The crawler crane was used to lift out the soil excavated,and the cap beams and linings were constructed in sections.The base of the anchor block and mass cavity-filling concrete in different zones were cast in layers and in sequence.The temperature control measures,like deploying cooling water pipes and preparing concrete with lower cement ratio,were taken to ensure the construction quality of the anchor block.

关 键 词：悬索桥 锚碇 地下连续墙 深基坑 内衬 大体积混凝土 施工技术 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U443.24[交通运输工程—道路与铁道工程]