五道白河特大桥29号主墩围堰施工技术

Construction Technology of No.29 Main Pier Cofferdam of Wudaobaihe Super-large Bridge

五道白河特大桥29号墩位于蓄水发电库区范围,围堰方案选用锁口钢管桩+锚固桩组合式围堰。在实际施工中,因管桩内引孔施工出现反复塌孔及无进尺现象,对方案进行了优化改进,采用取消锚固桩、利用引孔复振方式结合锁口及桩底堵漏措施,确保了硬质地层的锁口钢管桩围堰的顺利施工,同时采取无封底排水开挖工艺降低了施工难度,取得了较好的施工效果,可为类似工程提供借鉴。

Pier No.29 of Wudaobaihe Super Large Bridge is located in the area of water storage and power generation area.The cofferdam scheme uses a combined cofferdam with steel pipe piles and anchor piles.In the actual construction,due to repeated collapse and no footage in the pilot hole construction of the pipe pile,the plan was optimized and improved.The use of anchoring pile cancellation,the use of pilot hole re-vibration mode combined with the lock and the bottom plugging measures ensured the The smooth construction of the locked steel pipe pile cofferdam in the texture layer,and the use of non-bottomed drainage excavation technology has reduced the difficulty of construction and achieved good construction results,which can provide a reference for similar projects.