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Publication of BE735113ApublicationCriticalpatent/BE735113A/xx
E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D9/00—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
E21D9/005—Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries by forcing prefabricated elements through the ground, e.g. by pushing lining from an access pit