Abstract: Process for guiding the excavation tool used in order to execute the trenches necessary for the construction, by successive or alternating panels, of a wall cast in the ground, according to which:a) an excavation tool fitted with a first guiding element is provided,b) at the end of a previously executed trench, a second guiding element is arranged extending substantially over the entire depth of this trench, and thenc) after construction of the panel in the previously executed trench, the guiding elements are mutually engaged; andd) the excavation tool is controlled so as to create a force tending to keep the guiding elements mutually engaged while the excavation of the following trench is performed.

Abstract: A device for forming cast-in-situ piles in civil engineering work includes an auger which consists of a conventional lower part and an upper part comprising a hollow inner element and a removable outer element in the form of an auger having a longitudinal discontinuity which enables it to be fitted over the hollow inner element. The hollow inner element may extend, fixedly, as an elongation of the lower part of the auger or be mounted telescopically in the latter.

Abstract: The invention is concerned with civil engineering. It relates to a system for guiding the excavation tool used for making the trenches necessary for the construction panel-by-panel of a wall cast in the ground, which comprises, in combination, a vertical guide member extending over the height of the trench to be made and fixed to the adjacent panel or to a formwork located at the end of the adjacent panel, and guide wheels mounted on the excavation tool and rolling on the said member, said guide wheels being retained positively by the guide member relative to any horizontal force tending to separate them, and some wheel being profiled so as to be capable of destroying any obstacle of hardened concrete present on the guide member.

Abstract: The invention relates in particular to a device for producing tie-rods anchored in the ground, which comprises a tubular protective element comprising a top part and a base part and provided on its base part with at least one injection aperture, and at least one element constituting a tie-rod situated inside the tubular element, wherein the part of the element constituting the tie-rod extending along the top part of the tubular element is surrounded by a protective casing, with lubricant inserted between the element constituting the tie-rod and the casing.