ENLARGING TUNNEL STRUCTURE FOR PARALLEL CONSTRUCTING SUBSIDIARY MAIN TUNNEL OF SIDETRACK STATION FOR SUBWAY TRAIN, AND CONSTRUCTION METHOD FOR THE SAME

摘要

Provided are an enlarging tunnel structure installed with a parallel subsidiary main track tunnel for a sidetrack station and a construction method for the same. Subsidiary main single line tunnels are disposed in a parallel manner in a station of a subway train of a main double track tunnel without a large section tunnel when a side track to evacuate a slow train is installed during an operation of a train to accelerate the train in a subway route of a wide area railway or an urban railway. Also, a tunnel is enlarged and a subsidiary main track is installed in the subway route in operation to allow the evacuation of the slow train in order to enable an express service and a slow service of the urban railway. Also, locations of turnouts of the up line and the down line are adjusted in a different manner to minimize the size of an enlarging cross section when the subsidiary main single line tunnel is connected to a main double track tunnel. Also, since the enlarging construction is performed after the installation of a steel protector, safety of a train in operation can be secured. Also, a rock relaxation area is reduced by applying a machine excavation process to minimize an effect on a conventional main track station when a new tunnel for a sidetrack station is constructed nearby.