Abstract The joints and fissures of a rock mass easily form passages for water inflow and endanger metro con? struction. Based on the Jingjia section of Qingdao Metro Line 13, a water-rich zone, the scope and means of the ground water supply are determined by geological radar detection. Targeted grouting is conducted; that is to say annular grouting is carried out at the upper end of the water seepage area to seal the upstream water inflow. Radial grouting to the group holes is adopted to effectively prevent grout leaking and improve grouting efficiency regarding water inflow in fractured rock masses in deep strata, and filled grouting is implemented at the back of the initial support and the area with shallow fractures to cut off the hydraulic connection and improve the impermeability of the primary support. Practice indicates that good results are obtained by systematic grouting, which insures that shallow fissure grouting goes after deep fracture grouting in order to control water inflow from surrounding rock.
Abstract:
The joints and fissures of a rock mass easily form passages for water inflow and endanger metro con? struction. Based on the Jingjia section of Qingdao Metro Line 13, a water-rich zone, the scope and means of the ground water supply are determined by geological radar detection. Targeted grouting is conducted; that is to say annular grouting is carried out at the upper end of the water seepage area to seal the upstream water inflow. Radial grouting to the group holes is adopted to effectively prevent grout leaking and improve grouting efficiency regarding water inflow in fractured rock masses in deep strata, and filled grouting is implemented at the back of the initial support and the area with shallow fractures to cut off the hydraulic connection and improve the impermeability of the primary support. Practice indicates that good results are obtained by systematic grouting, which insures that shallow fissure grouting goes after deep fracture grouting in order to control water inflow from surrounding rock.