地铁隧道下穿软硬结合富水砂层关键技术研究  

Key Technology of Metro Tunnel Passing Through Soft-Hard Combined Water-Rich Sand Layer

作　　者：李科翰 LI Kehan(China Railway 19th Bureau Group Co.Ltd.,Beijing 100176,China)

机构地区：[1]中铁十九局集团有限公司,北京100176

出　　处：《铁道建筑技术》2024年第6期145-148,182,共5页Railway Construction Technology

摘　　要：青岛地铁1号线中胜区间埋深较浅,拱部覆岩仅为0.3~2.2 m,原为海边滩涂地,地表砂层厚、含水丰富,隧道洞身位于岩层中,为典型的软硬结合拱部富水砂层地质。针对这种特殊地质,注浆是治理此类地质灾害的最常用手段,但富水砂层注浆施工长期处于盲目、经验阶段,注浆设计缺乏理论依据,注浆加固效果不能有效保证,因城市环境复杂,隧道下穿施工安全难以保障。本工程采取富水砂层超前置换注浆加固拱部地层及逆台阶逐层剥离控制爆破技术以减少对拱部不良地质的反复扰动,充分保证岩层的自承能力,从而确保开挖安全。本技术对软硬结合拱部富水砂层条件下地铁隧道施工具有一定借鉴意义。The tunnel body of Qingdao Metro Line 1 in Zhongsheng section is located in the rock stratum because of the shallow depth and the overlying rock of the arch is only 0.3-2.2 m,which belongs to a typical soft-hard combined arch water-rich sand stratum geology for it used to be a beach land,with thick sand layer on the surface and rich in water.In view of this kind of special geology,grouting is the most commonly used method to control this kind of geological disaster,but the grouting construction in the water-rich sand layer is in the blind and experienced stage for a long time,and the grouting design lacks the theoretical basis,the effect of grouting reinforcement can not be guaranteed effectively,because of the complex urban environment,the safety of tunnel construction can not be guaranteed.In this project,advanced replacement grouting in waterrich sand layer is used to reinforce the arch stratum and anti-step controlled blasting technology is used to peel off layer by layer to reduce the repeated disturbance to the arch bad geology and fully ensure the self-supporting ability of the stratum,thus ensuring the safety of excavation.This technique can be used for reference in the construction of metro tunnel under the condition of water-rich sand layer in soft-hard combined arch.

关 键 词：地铁隧道 富水砂层 超前置换注浆 逆台阶 控制爆破 

分 类 号：U455.49[建筑科学—桥梁与隧道工程]