广乐高速公路马渡互通桥工程8m以上大溶洞施工技术

Over eight meters large karst cave construction technology of GuangLe highway exchange bridge engineering

马渡枢纽互通桥工程8m以上大型溶洞共有23个,其中有全填充13个、半充填7个和无充填3个。勘察揭露充填物质多为黏性土、砂、灰岩碎块及卵石土。岩溶发育情况显示岩溶顶板厚度小、洞体高度大,且充填不好,在受到外力作用情况下,可造成顶板塌落、地面发生塌陷,对于结构稳定性和桩基施工影响较大。施工中,全填充溶洞采取注浆加固处理;半填充溶洞采取先注浆加固,后对未填充部分灌注低标号细石混凝土处理;未填充溶洞全部灌注低标号细石混凝土处理,取得了良好的效果。

Madu communication bridge engineering has twenty three karst cave over eight meters,including the filling 13,half filled seven and no filling 3.Investigation revealed filling material is clayey soil,sand and gravel soils and limestone pieces.Karst development situation of karst thickness,that dongti height,and filling in the external force,by circumstance,can cause the roof collapsing,collapsing,for structural stability and pile foundation construction.Construction of the karst grouting reinforcement to fill;half filled cave after grouting strengthening,take part in not filled perfusion label fine stone concrete processing;no filling cave perfusion label fine stone concrete processing.Achieved good effect.