Abstract: A method for drilling into the ground includes digging a longitudinal hole in the ground, and simultaneously lining the hole with a tube extending substantially over an entire longitudinal length of the hole. The tube includes an inner tube and an outer tubular sheath inserted between the inner tube and a wall of the hole. After digging the hole, the inner tube is removed from the hole, with the outer sheath remaining in place inside the hole.

Abstract: The inflatable sleeve (13) comprises: a mandrel (15) extending in a longitudinal direction; an inflatable casing (17) placed around the mandrel (15); a tubular sheath (19) slid around the casing (17), the tubular sheath (19) having a central segment (27) and first and second longitudinal ends (23, 25) situated on either side of the central segment (27), the first and/or second ends (23, 25) of the tubular sheath (19) being fixed to the mandrel (15), the tubular sheath (19) being extensible from a rest state to an expanded state. The tubular sheath (19) has a predetermined circumferential elongation capacity from the rest state of the tubular sheath (19); and the first and/or second ends (23, 25) of the tubular sheath (19) have a longitudinal elongation capacity from the rest state of the tubular sheath (19) comprised between 1.05 and 2.5, chosen to limit the diametric expansion of the first and/or second ends (23, 25) of the tubular sheath and give the first and/or second ends their shape (23, 25).

Abstract: Hybrid elastic cable comprising at least one elastic filament yarn (1) and at least one resistant filament yarn (2), the elastic filament yarn (1), at a maximum rate of elongation of the cable, is found to be wound in a helix around the resistant filament yarn (2) with a specific number of turns per linear meter of the cable (nsE) ranging between nsE?15% and nsE+15%, nsE being determined based on a specific formula, wherein the elastic filament yarn (1) moreover is also twisted about itself with a specific number of distinct turns about itself per linear meter of the cable ranging between nsE and 3×nsE, and the distinct turns about itself of the elastic filament yarn (1) is wound in the opposite direction from that of the said helix.

Abstract: The inflatable sleeve (13) comprises: a mandrel (15) extending in a longitudinal direction; an inflatable casing (17) placed around the mandrel (15); a tubular sheath (19) slid around the casing (17), the tubular sheath (19) having a central segment (27) and first and second longitudinal ends (23, 25) situated on either side of the central segment (27), the first and/or second ends (23, 25) of the tubular sheath (19) being fixed to the mandrel (15), the tubular sheath (19) being extensible from a rest state to an expanded state. The tubular sheath (19) has a predetermined circumferential elongation capacity from the rest state of the tubular sheath (19); and the first and/or second ends (23, 25) of the tubular sheath (19) have a longitudinal elongation capacity from the rest state of the tubular sheath (19) comprised between 1.05 and 2.5, chosen to limit the diametric expansion of the first and/or second ends (23, 25) of the tubular sheath and give the first and/or second ends their shape (23, 25).

Abstract: Hybrid elastic cable comprising at least one elastic filament yarn (1) and at least one resistant filament yarn (2), the elastic filament yarn (1), at a maximum rate of elongation of the cable, is found to be wound in a helix around the resistant filament yarn (2) with a specific number of turns per linear metre of the cable ranging between nsE?15% and nsE+15%, nsE being determined based on the following formula: n sE = 1000 ? ? ( ? e + ? K ) × K max × ( K max + 200 ) K max + 100 in which ?e is the diameter in mm of the elastic filament yarn (1) at rest, ?K is the diameter in mm of the resistant filament yarn (2), and Kmax is the predetermined maximum rate of elongation of the hybrid cable, the elastic filament yarn (1) moreover being also twisted about itself with a specific number of distinct turns about itself per linear metre of the cable ranging between nsE and 3×nsE, the distinct turns about itself of the elastic filament yarn (1) being wound in the opposite d