都市快轨交通·第31卷第6期2018年12月 doi: 10.3969/j.issn.1672-6073.2018.06.019
《土建技术
MJS工法在砂卵石地层盾构近距离下穿运营地铁隧道的应用
周朋
（中铁第四勘察设计院集团有限公司，武汉430063）
摘要：依托在建长沙轨道交通4号线盾构区间，对砂卵石复杂地层下穿既有2号线运营区间预加固保护措施进行研究，并对多种预加固方案综合比选，最终采用MJS(全方位高压旋喷加固)工法对既有2号线进行预加固保护。工程实践表明，MJS工法水平加固过程中，既有2号线变形可控，最大变形约7mm，加固体强度可达5～8MPa 确保了4号线盾构穿越过程中既有区间的运营安全，这是国内首次在该类地层采用MJS工法对小净距既有运营线路进行水平预加固，可为今后类似工程提供参考和借鉴
关键词：MJS工法；砂卵石地层：近距离下穿；运营地铁隧道
中图分类号：U231
文献标志码：A
文章编号：1672-6073(2018)06-0122-07
Application of MJS Method in Traversing Under the Operating
MetroLineNeartheSandGravelLayer
ZHOUPeng
(China Railway Siyuan Survey & Design Group Co., Ltd., Wuhan 430063)
Abstract: For urban rail traffic, under-traversing the operating metro line always poses a serious risk, and is also an important research direction. In this article, a study and comparison of multiple reinforcement schemes for the shield tunnel of metro line 4 under-traversing the tunnel of operating metro line 2 in ChangSha city at the sand gravel layer is presented. The metro jet system or MJS method was adapted for the pre-reinforcement of the existing line 2. Practical application shows that the largest deformation of existing tunnel reached approximately 7 mm and the strength of the reinforced ground reached approximately 5~8 MPa, which controlled the deformation within the construction allowance and ensured the operational safety of the existing tunnel during the construction process. The MJS method is the first used for the pre-reinforcement of the operating metro line with a small clear spacing tunnel at this suite in China. This article will provide some experience in the field and ideas for similar projects
Keywords: metro jet system; under-traverse; sand gravel layer; under-traversing nearly; operating metro tunnelating metro tunnel
随着城市轨道交通的快速发展，在建及规划轨道交通线路与既有运营线路不可避免会存在平面交叉，从而出现近距离穿越既有运营线路工程，如广州珠江新城旅客自动输送系统(APM线)下穿既有1号线区间，北京地铁14号线下穿15号线区间[2]，上海地铁M4
收稿日期：2017-11-28
修回日期：2017-12-15
作者简介：周朋，硕士，工程师，从事隧道与地下工程设计研究
工作，zp_tsy@163.com URBAN RAPID RAIL TRANSIT
线下穿M2线区间[3]，武汉地铁3号线下穿既有2号线区间4等。目前很多学者对该类工程已有较为深入研究，虽然盾构穿越既有运营线路施工工艺逐渐成熟，但是在砂卵石复杂地层近距离穿越既有运营线路的相
关案例仍比较少见。 1工程概况
长沙地铁4号线作为长沙主城区辐射西北、东南的骨干线路(见图1)，4号线滦湾镇站一湖南师大站区