富水流砂粉细砂地层隧道降水施工技术  

Precipitation Construction Technology of Tunnels in Fluid-rich Sand and Fine Sand Formation

作　　者：李彩红 孙中华 孙冬梅 LI Caihong;SUN Zhonghua;SUN Dongmei(Economic&Technology Research Institute,State Grid Shandong Electric Power Co.,Jinan,Shandong 250000,China;Sixth Engineering Co.,Ltd.of China Railway No.3 Engineering Group Co.,Ltd.,Jinzhong,Shanxi 030600,China;Zhengzhou City Rail Transit Co.,Ltd.,Operating Co.,Zhengzhou,He’nan 450000,China)

机构地区：[1]国网山东省电力公司经济技术研究院,山东济南250000 [2]中铁三局集团第六工程有限公司,山西晋中030600 [3]郑州市轨道交通有限公司运营分公司,河南郑州450000

出　　处：《施工技术》2020年第S01期787-789,共3页Construction Technology

基　　金：国家电网有限公司科技项目(SGSDJY00SJJS1900042)

摘　　要：隧道工程施工中降水措施,最常用的井点降水方法有轻型井点、电渗井点、喷射井点、自渗井点、管井井点等,各种降水方法都有各自的适用土层。程儿山隧道为第三系细砂岩地层,岩质破碎疏松,归属极软岩,稳定性很差,在水的作用下极易软化;当地下水丰富或土层含水率高时,围岩软化现象明显,砂岩多呈淤沙状,基底有涌砂涌水现象发生,受水浸成淤泥,以上情况为富水粉细砂地层隧道施工遇到的难题,介绍负压真空降水、洞顶垂直降水及重力式井点降水的联合降水技术,为隧道开挖掌子面提供无水作业面,保证施工安全和施工进度,工艺简洁明了,对此种地层实用性较强,效果较好。In the process of dewatering in tunnel construction,the most common dewatering methods are light well point,electro-osmotic well point,jet well point,self-seepage well point,tube well point,etc..The Chengershan tunnel is a fine sandstone stratum of tertiary system,the rock is broken and loose,belongs to extremely soft rock,its stability is very poor,and it is easy to be softened under the action of water,when the ground water is rich or the water content of the soil layer is high,the softening phenomenon of the surrounding rock is obvious,the sandstone is mostly silt-like,there is a phenomenon of sand gushing and water gushing in the basement,which has been immersed into silt.The above situation is a difficult problem encountered in the construction of tunnels in water-rich silty and fine sand stratum,this paper introduces a combined precipitation technology of negative pressure vacuum precipitation,vertical precipitation of tunnel roof and gravity well point precipitation,which provides no-water working surface for tunnel excavation face,construction safety and construction progress is ensured,and the technology is simple and clear,for this kind of stratum,the practicability is strong,the effect is good,and it has great value of popularization and application.

关 键 词：隧道 降水 重力式 降水井 

分 类 号：U455.49[建筑科学—桥梁与隧道工程]