An Improved Method of and Apparatus for Driving Tunnels for Military or other purposes in Earth or Soft Rock.

摘要

127,323. Hopkinson, A. April 19, 1917. Tunnels.-The lining of a tunnel for military or other purposes comprises sections formed of two or more hinged members 41 and a loose member 42 inserted in a slotted hinge 43 and held between fixed and sliding flanges 44, 45; each lining section fits within the preceding section. The space below the tunnel floor 46 is connected to a drain pipe 33, Fig. 3, and also to a pipe 34 connected to a fan for ventilating the tunnel.