Construction Technology of the Loess Subway Tunnel in Special Geological Conditions

Research purposes: Based on summing up the construction method and the measures used for the loess tunnel of Xi'an subway tunnel and treatments of the water bursting when the shaft passing through the F3 ground fissures,this paper offers a set of reasonable,feasible and safe construction methods to ensure the safety of the shaft and tunnel construction for accumulating the experience to the similar projects. Research conclusions:Application of the churning jet pile outside the shaft makes the ground water and water bursting from the fissures going out from the outside of the water curtain of the churning jet pile.At the same time,by taking the measures of the grouting reinforcement in the shaf,the precipitation in shafts,the partial excavation,the grouting down outside shafts by the flower arrangement tubes,the back cover of concrete bottom of the shaft,the drainage of groundwater in advance and the precipitation inside the tunnel,the problems of the water bursting in construction of the shaft and tunnel in the water-enrich coarse strata of loess areas are overcome.