武汉鹦鹉洲长江大桥1#墩塔施工技术

Construction Technology of No.1 Pier Tower of Wuhan Yingwuzhou Yangtze River Bridge

鹦鹉洲长江大桥主桥长2 100 m,采用（200＋2×850＋200）m三塔四跨钢板结合梁悬索桥。1#塔墩位于汉阳江滩护坡上,地表标高12.0-21.0 m,高差起伏较大,基础施工对岸坡影响大,采用了＂前排桩＋锚杆＂的结构形式以保证大堤稳定。1#墩基础采用44根直径2.0 m钻孔灌注桩,钻孔深度超过80 m,采用筑岛、双排防护桩施工方案。1#塔塔柱高达126.2 m,截面尺寸大、混凝土方量大,施工采用爬模分节段施工。1#墩钻孔桩施工、围堰施工与岸坡防护的相互配合、承台大体积混凝土浇筑控温等均是本工程的施工重点与难点。

Yingwuzhou Yangtze River Bridge,with 2 100 mmain bridge span using（ 200 ＋ 2 × 850 ＋ 200） m,is a suspension bridge using three towers and four-span steel composite girder. The 1# tower pier section is located on Hanyang marshland slope,with surface elevation 12. 0 mthrough 21 m. The great elevation difference has side effect,the construction of foundation affecting the slope. Thus,＂front rowpile ＋ anchor rod ＂structure was used to ensure the embankment stability. 1# pier foundation uses 44 2. 0-m-diameter bored piles and the drilling depth is more than 80 m. Island was built and double-line protect piles were used. The 1# tower is 126. 2 mhigh,resulting large sectional dimension and concrete volume; thus,segmental climbing formwork was used. The cooperation of the1# pier bored piles construction,cofferdamconstruction and slope protection,and temperature control in mass concrete pouring of the bearing platformare the keys and difficulties of the project.