摘要
南京地铁3号线某中间风井超深基坑，地下连续墙深44．2m，嵌入中风化硬岩达10～13m，介绍了超深基坑大深度入岩地下连续墙的关键施工技术。施工实践表明，冲抓结合法有效解决了大深度入岩地下连续墙成槽问题；钢筋笼采用一次制作成型、分段吊装空中连接降低了吊装难度和风险；水泥土搅拌桩加固较厚软弱土层防止槽壁长时间暴露坍孔问题；刚性止水接头加焊止浆板防止混凝土绕流等措施，结果表明墙体质量、垂直度和止水效果均满足设计要求，保证了超深基坑的安全顺利开挖。
For the ultra-deep foundation excavation of one middle shaft of Nanjing Metro Line 3, the depth of diaphragm wall is 44.2m, which embeds the weathered hard rock in 10 -13m, this paper introduces the key construction technology for large depth rock entering diaphragm wall of ultra-deep foundation excavation. Engineering practice shows that drill-grab combination can solve the trenching of large depth rock entering diaphragm wall effectively; the steel reinforcement cage is once-for-all formed, segment hoisted thus reduces the hoisting difficulty and risk; cement mixing pile strengthening the thick soft soil layer prevents the hole collapse due to long time exposure of slot wall; the rigid water stopping joint with weld pulp board can prevent burble by concrete. The results show that the quality, verticality and water stopping of the wall meet the design requirement, and ensure smooth excavation of ultra-deep foundation excavation.
出处
《施工技术》
CAS
北大核心
2014年第11期115-118,共4页
Construction Technology
关键词
基坑
地下连续墙
冲抓结合
施工技术
foundation excavation
diaphragm walls
drill-grab combination
construction
