Apparatus for driving and lining tunnels in unstable soil

Claim 1

A TUNNELLING MACHINE ADAPTED TO CUT AND REMOVE SOIL OR SOFT ROCK, SUPPORT THE SURROUNDING SOIL OR SOFT ROCK OF THE UNLINED BORE HOLE, AIRTIGHTLY ISOLATE THE FACE OF THE BORE HOLE FROM THE REAR OF THE BORE HOLE AND PROVIDE FORMS AND CURING FACILITIES FOR THE PERMANENT CONCRETE LINING AS THE TUNNELLING MACHINE MOVES FORWARD, THE SAID TUNNELLING MACHINE COMPRISING A RIGID LEADING TUBE SHAPED TO THE OUTSIDE DIMENSIONS OF THE PERMANENT CONCRETE TUNNEL LINING AND FURNISHED WITH A CUTTING EDGE AT ITS FRONT END, A SECOND RIGID TUBE SHAPED TO THE SAME DIMENSIONS SLIDABLY OVERLAPPED AT ITS FORWARD END BY THE TAIL END OF THE SAID LEADING TUBE AND EXTENDING REARWARDLY BEYOND THE FRONT FACE OF THE PERMANENT CONCRETE TUNNEL LINING PROVIDING TEMPORARY SUPPORT FOR THESURROUNDING SOIL OR SOFT ROCK OF THE BORE HOLE, A THIRD RIGID TUBE SHAPED TO AND CONSTITUTING A SLIP FORM FOR THE PERMANENT CONCRETE TUNNEL LINING PROJECTING FORWARDLY FROM THE FRONT FACE OF THE SAID CONCRETE TUNNEL LINING AND EXTENDING REARWARDLY INTO THE FINISHED LINES TUNNEL AT WHICH THE REARWARD PORTION IS SLIGHTLY SMALLER IN ITS CROSS-SECTIONAL AREA THUS PROVIDING A SPACE BETWEEN THE INNER FACE OF THE SAID CONCRETE TUNNEL LINING AND THE SAID SLIP-FORM FOR INJECTING HIGH PRESSURE STEAM AS A CURING AGENT, A RIGID BULKHEAD RING SLIDABLY LOCATED BETWEEN THE REAR END OF THE SECOND TUBE AND THE FORWARD END OF THE THIRD TUBE CONSTITUTING A FORM FOR THE FRONT FACE OF THE PERMANENT CONCRETE TUNNEL LINING AND PROVIDING A BEARING SURFACE FOR THE JACKING MECHANISM AFTER THE SAID SPACE IS FILLED WITH CONCRETE, A PLURALITY OF JACKING MECHANISMS FOR THE ADVANCEMENT OF THE SECOND TUBE MOUNTED PERIPHERICALLY THEREON AND DETACHABLY CONNECTED TO AND BEARING ON THE SAID BULKHEAD RING, ANOTHER PLURALITY OF JACKING MECHANISMS FOR THE ADVANCEMENT OF THE LEADING TUBE PERIPHERICALLY MOUNTED THEREON AND BEARING ON THE SECOND TUBE WHILE THE LATTER IS HELD IN PLACE BY THE FIRST MENTIONED JACKING MECHANISMS, A FURTHER PLURALITY OF JACKING MECHANISMS FOR THE ADVANCEMENT OF THE THIRD TUBE, DETACHABLY CONNECTED THEREON AND SUPPORTED BY THE SECOND TUBE, A CLOSED AIRTIGHT SHIELD DETACHABLY MOUNTED NEAR THE TAIL END OF THE LEADING TUBE ISOLATING THE FACE OF THE BORE HOLE FROM THE REARWARD PORTION OF THE TUNNEL, A VARIETY OF MINING EQUIPMENT MOUNTED TO AND PENETRATING THE SAID SHIELD TO CUT SOIL AND SOFT ROCK IN FRONT OF THE SAID SHIELD, A HYDRAULIC DREDGING MECHANISM, CONNECTED TO A RIGID PIPE PENETRATING AND ADVANCING WITH THE SAID SHIELD, A COLLECTING HOPPER ATTACHED TO A SECOND PUMP LOCATED REARWARDLY FROM THE TAIL END OF THE THIRD TUBE RECEIVING THE EFFLUENT FROM THE FIRST PUMP THE SECOND PUMP BEING CONNECTED WITH A STATIONARY DISCHARGE LINE LEADING TO THE DISPOSAL FACILITIES, A WAER SUPPLY PIPE RIGIDLY CONNECTED TO THE LEADING TUBE AND FLEXIBLY CONNECTED TO A STATIONARY WATER SUPPLY PIPE REARWARDS OF THE THIRD TUBE SUPPLYING WATER TO THE BORE HOLE FORWARD OF THE SAID SHIELD FOR HYDRAULIC REMOVAL OF THE EXCAVATED MATERIAL, AND A CONCRETE SUPPLY LINE CONNECTED TO THE FRONT END OF THE THIRD TUBE FOR CONVEYING CONCRETE TO THE SPACE BEHIND THE SAID BULKHEAD RING.