中央电视塔塔身竖向预应力混凝土结构施工

Vertically prestressed concrete construction for the CCTV transmission tower shaft

中央电视塔塔身和桅杆采用部分预应力混凝土结构。塔身竖向预应力束最长达271.8m。由于采用与滑框倒模同步进行的竖向预应力管道铺设、自下而上机械牵引穿束工艺、塔体和桅杆预应力筋张拉、竖向孔道分段逐层灌浆等成套技术,保证了中央电视塔竖向预应力混凝土结构施工的顺利进行,并取得了显著的技术经济效益。

The CCTV transmission tower shaft and its mast are mainly built of a vertically prestressed reinforced concrete structure. The total vertical length of the prestressed tendon of the tower shaft is 271.8m. There are several major operational procedures worthy to be mentioned here, i. e. (1) synchronized operation of the reversible slipform process with the placing of vertical tendon-ducts simultaneously, (2) application of the double acting jacks from bottom to top and, step by step, the tower shaft and its mast being vertically prestressed properly, (3) seperatestages of tendonducts' grouting successively completed duly on time. As a result, it has been completed smoothly and gained with cconomic benefit.