2016年9月上 施工技术 第45卷第17期 CONSTRUCTION TECHNOLOGY 35 DOI:10. 7672/sgjs2016170035 土岩地层超深基坑结构反向对接施工技术 施群凯,杨前,范作锋,王乾,丁丽祯 (中国二十冶集团有限公司,上海201901) [摘要】随着国家建设事业的不断发展,建设区域所处位置的地质条件与周围环境条件越来越复杂,在近年来承建 的多项超深基坑工程项目中,施工区域所处环境复杂,所建工程需进行半开挖、半爆破施工。
而且位于基坑下半部 的岩层内岩溶裂隙发育,岩层内含有大量岩溶裂隙水,对施工的安全及环境影响保护要求极高。
以南钢宽厚板工 程旋流池基坑为例,针对工程中所遇到的技术难题及今后深基坑专业发展趋势进行了总结。
[关键词]超深基坑;反向对接;爆破防护;施工技术 [中图分类号】TU753 [文献标识码】A [文章编号】1002-8498(2016)17-0035-05 Reverse Docking ConstructionTechnology ofUltra-deepFoundation Excavation Structures in Soil-rock Stratum Shi Qunkai,Yang Qian,Fan Zuofeng,Wang Qian,Ding Lizhen (China MCC20 Group Co.,Ltd.,Shanghai 201901, China) Abstract;Along with the continuous development of the state construction,geographic conditions of construction areas and their surrounding environmental conditions bee more and more plex. In the few ultra-deep foundation excavation projects constructed in recent years,the circumstances of the construction areas were so plicated that the projects had to be carried out by the bination of excavation and blasting.Besides, the karst fissure development of the rock strata at the lower part of the foundation excavation and the plenty of karst fissure water within the strata lead to rather high requirements for construction safety and environmental protection.This technique takes the swirl pool foundation excavation of Nanjing Steel Wide and Heavy Plate Project as an example and summarizes the technical problems encountered in the project as well as professional development trend of deep foundation excavations in future. Key words;ultra-deep foundation excavation; reverse docking; blasting protection;construction 1工程概况 采用局部深度基坑放坡开挖,即上段挖土卸载放坡 本工程为南钢节能降耗调整产品结构技术改或直立开挖,需要时对坡面进行加固保护,下部基 造项目4700mm轧机工程一标段旋流池工程,旋流坑土体较好时不放坡开挖,故本工程采用了先进行 池位于水处理区域,平流池南侧,结构从上向下依上部松软土放坡开挖、施工结构后,再进行下半部 次由上层顶板、中部1层泵站平台、水池底板及池内爆破开挖后施工结构,最终进行结构对接的方法。
冲渣沟组成,外筒直径为18m,壁厚800mm,内筒直 工艺流程:上部土方开挖→平整岩石层、浇筑 径为6m,壁厚400mm,池底埋置深度为-26.000m, 垫层→反梁、上部结构施工→回填夯实上部结构外 底板厚1200mm。
由于本旋流沉淀池埋藏较深,其围...