E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
E21D15/00—Props; Chocks, e.g. made of flexible containers filled with backfilling material
E21D15/14—Telescopic props
E21D15/28—Telescopic props with parts held relatively to each other by friction or gripping
E21D15/32—Telescopic props with parts held relatively to each other by friction or gripping by a deformable collar or clamping means applied symmetrically inside a locking ring
Jonction transversale comprenant deux extrémités transversales se faisant face de deux éléments successifs préfabriqués de chaussée et son système de liaison