摘要
以南京地铁1号线许府巷—南京站区间隧道为背景,结合现场监测数据及各项掘进参数设置,对土压平衡盾构在富水饱和粉土、粉砂夹细砂、粉细砂地层中掘进引起的地表变形过程和分布规律进行分析,并使用有限差分法程序FLAC3D对考虑盾构施工工序、地下水位、土仓压力和注浆等因素的地表变形进行模拟计算分析。实测分析结果表明地表变形特征为:沉降速率大,测点最大沉降速率在-12^-15 mm.d-1之间;地层稳定快,盾尾脱出2~3 d后地层即趋于稳定;影响范围小,盾构掘进对隧道纵向地表的扰动在刀盘前方约10 m至盾尾后方16~20 m的范围内,横向地表沉降主要分布在隧道中心线两侧各5~7 m的范围内,地表距中心线20 m以外几乎不受影响。模拟计算地表沉降分布结果与实测数据基本吻合。
On the basis of the monitoring data and tunneling parameters of the section tunnel from Xufuxiang to Nanjing railway station in Nanjing No. 1 Subway, this paper analyzes the process and distribution of the ground deformation induced by tunneling with the EPB shield machine through the saturated silty clay layer, silty clay and fine sand interbedded strata and the fine sand layer. Considering the factors of shield opening, groundwater level, pressure of soil chamber, grouting effectiveness etc, the ground deformation is simulated by the use of finite difference code FLAC^3D. The measured results show the characteristics of ground deformation： high settling velocity with the maximum settling velocity -12～-15mm·d^-1 , rapid stabilization of disturbed ground with the ground stable in about 2 to 3 days after the pass of shield tail, and small affected area with the longitudinal settlement area ranging from 10 m ahead of the shield clutter to 16-20 m behind of shield tail along the tunnel alignment. The lateral settlement mainly distributes within 5-7 m from the tunnel center line and the ground is almost not disturbed in the area about 20 m beyond the center line. The simulated deformation results agree well with the measured data.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2006年第5期87-92,共6页
China Railway Science
关键词
地表变形
有限差分法
土压平衡盾构
隧道施工
Ground deformation
Finite element-difference method
EPB shield construction
Tunnel excavation
