Patent ID: 8690478

Claim:
A tunnel construction method capable of controlling displacement using pressurization so as to excavate the ground or tunnel under a given structure, the tunnel construction method comprising the steps of: (a) forcedly inserting a plurality of reinforcements into the bored holes formed along an outer surface of the section to be excavated of the tunnel in one direction or in both directions, so as to safely control the displacement of the tunnel, each of the reinforcements having a diameter in a range between 50 mm and 300 mm and a length in a range between 12 m to 40 m; (b) injecting a reinforcement material in which cement milk is contained into the interior of each reinforcement; (c) mounting a plurality of face bolts on an excavation face of the tunnel in an excavation direction so as to prevent the excavation face during excavation from collapsing or being displaced; (d) excavating the tunnel; (e) installing steel ribs on the excavated area of the tunnel; (f) mounting a pressurizing bag between the steel ribs and the excavated inner surface of the tunnel and injecting cement milk into the pressurizing bag to pressurize the pressurizing bag; (g) inserting a steel cage between the adjacent steel ribs and casting shotcrete to the steel cage; (h) installing a plurality of auxiliary reinforcements disposed between the reinforcements from a point between 4 m and 8 m inwardly from the ends of the reinforcements forcedly inserted into the tunnel in such a manner as to be inclined by 8° to 12° from the excavation face, if the tunnel has a longer length than one or two reinforcements; (i) injecting the reinforcement material into the auxiliary reinforcements installed inclinedly; and (j) after the steps (d) to (g) are repeatedly carried out until the excavation for the tunnel is finished, casting lining concrete to the steel ribs and the inner surface of the shotcrete, wherein at the step (a) the reinforcements are forcedly inserted into the bored holes formed along the outer surface of the section to be excavated on the tunnel in such a manner as to be spaced apart from each other by a distance between a diameter of each auxiliary reinforcement and 100 cm in a parallel direction to the excavation direction of the tunnel.