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
E21D15/16—Telescopic props with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure
E21D15/24—Telescopic props with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure with axial screw-and-nut, rack-and-worm, or like mechanism
E21D15/26—Telescopic props with parts held together by positive means, with or without relative sliding movement when the prop is subject to excessive pressure with axial screw-and-nut, rack-and-worm, or like mechanism with screw, worm, or the like, not self-locking but normally prevented from rotation by friction members which slip upon excessive pressure
Dispositif de blocage en rotation d'un assemblage visse, assemblage comprenant un tel dispositif et utilisation d'un tel assemblage dans la construction aeronautique