Abstract: The present invention provides a head for injecting a fluid under pressure for breaking up the ground from a borehole and mounted at the end of a string of rods. The body of the drilling head has a bottom wall for mounting a mechanical drilling tool having a feed pipe, at least one injection nozzle, and duct-forming means for connecting the feed pipe with liquid at the inlet of said nozzle, the duct-forming means presenting a mean line having a radius of curvature that varies continuously, the right section of said duct-forming means decreasing regularly over at least half its length from its first end towards its second end. The injection head further comprises at least one pipe for feeding said mechanical tool, said pipe being connected at a first end to said duct-forming means and at a second end to a chamber disposed at the bottom end of said injection head and fitted with a controllable shutter member interposed between said chamber and the pipe for feeding said mechanical tool.

Abstract: The present invention provides a head for injecting a fluid under pressure for breaking up the ground from a borehole and mounted at the end of a string of rods. The body of the drilling head has a bottom wall for mounting a mechanical drilling tool having a feed pipe, at least one injection nozzle, and duct-forming means for connecting the feed pipe with liquid at the inlet of said nozzle, the duct-forming means presenting a mean line having a radius of curvature that varies continuously, the right section of said duct-forming means decreasing regularly over at least half its length from its first end towards its second end. The injection head further comprises at least one pipe for feeding said mechanical tool, said pipe being connected at a first end to said duct-forming means and at a second end to a chamber disposed at the bottom end of said injection head and fitted with a controllable shutter member interposed between said chamber and the pipe for feeding said mechanical tool.

Abstract: An apparatus for drilling trenches in the ground comprising a main frame having two vertical main faces, a drilling assembly comprising a support disposed at the bottom of said frame, means for causing said drilling assembly to move in vertical translation relative to said main frame by applying a predetermined force to said drilling assembly relative to said main frame, and anchoring means mounted on said main faces for anchoring the main frame to the walls of said trench. The anchoring means comprise a plurality of deformable elements secured to said main faces of the top frame, means for injecting a fluid under pressure into said inflatable elements thereby applying a force between said main frame and the walls of the trench, and means enabling said fluid under pressure to escape from said inflatable elements whereby no force is transmitted between said main frame and the walls of the trench.

Abstract: The invention provides apparatus for drilling trenches in the ground, the apparatus comprising a frame and a drilling assembly having a horizontal support plate connected to the bottom end of the frame, said plate supporting drilling tools disposed beneath said plate, said trench being filled with a drilling mud. The periphery of said plate has resilient sealing means for co-operating with the walls of the trench so as to provide at least partial sealing between said plate and the walls of the trench, and means for adjusting drilling mud flow rates from the portion of the trench situated above said plate to the portion of the trench situated beneath said plate, and also in the opposite direction.

Abstract: The invention provides a head for injecting a liquid under pressure from a borehole to break up the soil, said head being mounted at the end of a drill string including a liquid feed for feeding a liquid under pressure. The head comprises a body and an outside wall, the body having at least one injection nozzle mounted therein, the nozzle having an inlet diameter equal to d and presenting an axis (x-x′), the body also having a tube. The tube presents a mean line having a first end connected to the bottom end of the liquid feed and having a second end connected to the nozzle tangentially to the axis (x-x′). The mean line is defined by at least one curved portion presenting a radius of curvature that varies continuously. The right section of the tube decreases regularly over at least half of its length from its first end to its second end.

Abstract: The invention provides an apparatus for drilling trenches in the ground, the apparatus comprising a main frame (10) having two vertical main faces (32, 32′), a drilling assembly (18) comprising a support disposed at the bottom of said frame, means (28, 30) for causing said drilling assembly to move in vertical translation relative to said main frame by applying a predetermined force to said drilling assembly relative to said main frame, and anchoring means for anchoring the main frame to the walls of said trench, said means being mounted on said main faces.

Abstract: The invention provides apparatus for drilling trenches (42) in the ground, the apparatus comprising a frame (14) and a drilling assembly having a horizontal support plate (18) connected to the bottom end of the frame, said plate supporting drilling tools (24, 26) disposed beneath said plate, said trench being filled with a drilling mud.

Abstract: The invention provides a head for injecting a liquid under pressure from a borehole to break up the soil, said head being mounted at the end of a drill string including liquid feed means for feeding a liquid under pressure. The head comprises a body and an outside wall, the body having at least one injection nozzle mounted therein, the nozzle having an inlet diameter equal to d and presenting an axis x,x′, the body also having duct-forming means. The duct-forming means present a mean line having a first end connected to the bottom end of the liquid feed means and having a second end connected to the nozzle tangentially to the axis x,x′. The mean line is defined by at least one curved portion presenting a radius of curvature that varies continuously. The right section of the duct-forming means decreases regularly over at least half of its length from its first end to its second end.

Abstract: The invention relates to a cast wall constituted by a succession of panels touching via their end edges and made by casting a binder in contiguous lengths of trench dug in the ground in line with one another, each panel including reinforcement, said wall further including link means between the reinforcements in two contiguous panels. The link means (24, 44) are separate from the reinforcement (22, 42) and comprise an anchor element (24) having a first end fitted with at least one vertical first locking element (28, 30) and a second end engaged in one of said panels (22), and a link element (44) having a first end provided with at least a second locking element (46, 48) suitable for co-operating with the first locking element, and a second end engaged in the other one of said panels (42).

Abstract: A device for drilling into the ground for the in-situ production of columns of stabilized and compacted soil, which comprises at least two parallel shafts, each shaft driving in rotation one auger, each auger being fitted with a loosening drill head. The shafts and the shanks of the augers include a bore and at least one orifice for discharging a filler material, the augers having opposite hands and being driven in counterrotation, and which furthermore have a drive for reversing the direction of rotation of the augers, said device including an even number n, at least equal to 4, of augers and in that, as seen in cross-section, the axes of the augers are centered at the vertices of a regular n-sided polygon.

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: 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 to civil engineering works.In particular, it relates to a device suitable for forming a primary column of stabilized and compacted soil, which comprises at least two parallel shafts driving in opposite directions, two parallel augers with opposite pitch, each auger being provided at the opposite end to the drive shaft with a loosening drillhead and the distance between the axes of the augers being less than the diameter of an auger, the shafts and the shanks of the augers comprising a bore connected to a source of material to be added, and at least one orifice which communicates with the said bore being provided on the shank of each auger so as to discharge the material to be added and allow it to be mixed with the loosened soil.Applicable in particular for the compaction of railroad territory.