Cutting chamber at the tunnel cutting face is formed by pressure cushions between the roof shields and the support frames to give a forward movement under pressure without tunnel roof damage

摘要

To secure a tunnel stretch (3), in underground tunneling and mining operations, a chamber (1) is formed between the cutting face (4) and the completed tunnel lining. Pressure cushions, filled with a pressure medium, are between the roof shields (11,12) and the support frames (10,26,27) to give the support frame (10,26,27) a forward movement under pressure. The cushions are constantly connected to a pressure pump, and are relaxed only partially on a reverse movement.