漂卵砾石地层沉井法施工大型调压井技术  

Construction Technology of Open Caisson Method of Large Surge Shaft in Gravel-Boulder Layer

作　　者：王志强[1] 杨兴国[1] 李洪涛[1] 姚强[1] 王勇胜[1] 

机构地区：[1]四川大学水利水电学院,四川成都610065

出　　处：《中国农村水利水电》2013年第8期103-106,109,共5页China Rural Water and Hydropower

基　　金：国家自然科学基金资助项目(51009104)

摘　　要：喜儿沟水电站调压井深度102m,调压井上部65m地质条件为冲洪积漂卵砾石层,用沉井法施工调压井,使开挖时的临时支护措施和井筒永久结构相结合,有效避免井壁坍塌,大大降低了安全风险。在漂卵石地层,采取先中间、后预留,对称、均匀地削薄土层,有效地避免了沉井被挟持的现象;在软硬相间不均匀地层,采取先硬基、后软基,有效地避免了刃脚变形和井壁开裂;在胶结砾岩地层,使用液压破碎锤破除胶结砾岩,有效地解决了反铲开挖困难、钻爆开挖效果不佳的问题。并针对出渣量大这一问题,因地制宜地采取了合理的出渣方案,大大提高了出渣效率。喜儿沟水电站调压井沉井法的顺利施工,可供同类工程参考。The depth of surge shaft in Xi＇ergou Hydropower Station is 102meters,the geological condition in 65meters above the surge shaft is alluvial-diluvial gravel-boulder layer,use the open caisson to construct the surge shaft,make the temporary support measures combine with the permanent structure of the shaft when excavating,then it can effectively avoid the hole-wall collapsing and enormously reduce the security risk.In the fluvial boulders layer,first we excavate the soil in the middle of the layer,then skiving the reserved soil symmetrically and evenly,that we can effectively avoid the open caisson was stuck;In the soft and hard alternated layer,first the hard base and then the soft base to avoid the foot blade deformation and cracking of the borehole wall effectively;during cement the conglomerate formation,we take the hydraulic breaking hammer to get rid of the difficulty of backhoe excavation and ineffectiveness of drill-blast excavation.Aim at the problem of large quantity slagging,we have taken reasonable slagging program scientifically which will greatly improve the efficiency of the slagging.The successfully constructed open caisson of surge shaft in Xi＇ergou Hydropower Station can provide a reference for the similar projects.

关 键 词：喜儿沟水电站 沉井 漂卵砾石地层 开挖出渣 

分 类 号：TU753.64[建筑科学—建筑技术科学]