悬索桥猫道绳水面浮托往复牵引架设技术

怀来官厅水库特大桥为主跨720 m的双塔单跨悬索桥,猫道长1230 m。大桥猫道钢丝绳架设受高空作业环境限制、水面无大型动力船牵引、水底构造物多等不利因素影响,经方案比选,采用水面浮托往复牵引法进行猫道钢丝绳的架设。在水面设置浮体,连接浮体与猫道钢丝绳,使钢丝绳浮托在水面,串联两岸卷扬机与钢丝绳,形成往复索引系统,牵引猫道钢丝绳过水架设。线路左侧猫道的钢丝绳由北往南架设,线路右侧猫道的钢丝绳由南往北架设,1次架设1根猫道钢丝绳。

Water-Surface-Floating Supported To-and-Fro Dragging and Erection Technique for Catwalk Ropes of Suspension Bridge

The Guanting Reservoir Bridge in Huailai County is a two-tower,single span suspension bridge with a main span of 720 m.The catwalk ropes are 1230 m long.The erection of the steel wire ropes of the catwalk was challenged by a variety of unfavorable factors,including the overhead working environment,lack of large-scale power-driven boats for dragging and the existing underwater structures.Based on the scheme comparison,the catwalk steel wire ropes were erected by the water-surface-floating supported to-and-fro dragging method.Floating blocks were placed on the water surface and linked with the catwalk steel wire ropes to make the steel wire ropes supported on the water surface.The winches on both banks were connected with the steel wire ropes to form the to-and-fro dragging system,then,the catwalk steel wire ropes could be dragged across the river for erection.The steel wire rope on the left side of the bridge was erected from the north towards south and that on the right side was erected from south towards north,one steel wire rope each time.