五峰山长江特大桥超大型沉井地基处理技术

摘要

The gravity type open caisson foundation is adopted as for the foundation of the north an-chorage of the Wufeng Shan Yangtze River Large Bridge.In the construction process of the north an-chorage caisson foundation,the ground bearing capacity is insufficient,the hydraulic fill sand,sand compaction pile,and replacement method are used to reinforce the ground.The results indicate that, the ground bearing capacity is sufficient to meet design and construction requirements.%五峰山长江特大桥桥北锚碇采用重力式沉井基础。锚碇区地质土层松软，地基承载力差，为保证地基承载力满足沉井拼装及接高浇筑要求，避免沉井下沉初期出现突沉现象，采用吹填砂施工、砂桩挤密加固、换填砂垫层及铺设素混凝土垫块等方法对地基进行加固。通过多种地基处理工艺相结合，至钢壳沉井隔舱混凝土浇筑完成，沉井累计均匀下沉101 mm，地基承载力满足设计和施工需要。