特大型溶洞隧道综合处治方案及施工技术

摘要

为解决岩溶地区公路隧道修建过程中特大型溶洞难跨越的问题,采用理论与现场相结合的方法,综合考虑特大型溶洞的特点与处治难点,提出采用"承载桩基-纵横框架梁板-钢筋混凝土挡墙"组合处治结构与洞渣回填综合处治的方案,在此基础上建立一套以回填为基础、自下而上交叉施工处治结构的施工方法,并提出洞渣回填、承载桩基、纵横框架梁板结构及钢筋混凝土挡墙结构施工等关键技术.现场施工实践证明,该溶洞处治效果良好,能保证隧道施工安全与结构安全.%Super-large karst caves are encountered during construction of Naqiu Tunnel on Yongji Highway.As a result,a combination structure of bearing pile foundation + vertical and horizontal frame-beam-plate structure + reinforced concrete retaining wall and slag backfilling are adopted based on characteristics and treating difficulties of large karst cave and theoretical and site studies.And then a set of construction methods of alternate up-down construction of the structure on basis of slag backfilling is established.The construction practice shows that the technologies used are rational and feasible and good effect has been achieved.