Abstract: Impermeabilization and/or consolidation product for soils and building materials, usable by injection, characterized by the fact that it is obtained by mixture of a compound of slag in suspension in water and of a silica liquor having a ratio of SiO.sub.2 Na.sub.2 O lower than 2 and a silica content greater than about 10% by weight.

Abstract: A cutting machine for cutting trenches in the ground, including a flat bottom face portion for supporting a pair of motor blocks; two motor blocks, with parallel axes, adapted to mount half-drum cutters; each motor block comprising a central vertical keel projecting downwardly from a horizontal top plate; connection means securing each motor block top plate to said bottom face; the inner edge of each top plate being provided with a beveled surface; an abutment member having parallel beveled edges complementary in shape to the beveled edge of each top plate; means mounting said abutment member to the central portions of said bottom surface; locking means urging the beveled edge of each top plate against the beveled edges of said abutment member.

Abstract: Apparatus including a rotary drilling cutter and a spoil removal conduit for the digging of a deep trench, characterized in that the spoil removal conduit is gradually adjustable in length during excavation and comprises: (a) a first conduit section, arranged proximate to said rotary cutter, and comprised of associated slidingly adjustable rigid male and female telescopic tube elements; (b) a second conduit section comprising a flexible tube having two ends, said flexible tube being connected to said first conduit section by one of its ends, its other end being disposed in the vicinity of the ground at a predetermined spoil discharge point, (c) a pulley supporting said flexible tube between said two ends; (d) lifting gear for suspending said pulley; and (e) a first cable associated with said lifting gear for supporting said pulley at selected adjustable heights.

Abstract: A process for attaching an injection pipe with injection valve means to the inside wall of a tubular pile section comprising: drilling holes at a plurality of points along a generatrix of the pile section said holes passing through the wall of the pile; preparing an injection pipe having substantially the same length as the section of the pile to which it is to be attached; connecting said injection pipe with injection valve to said pipe, the spacings between said valve means corresponding to those of the said holes drilled in the wall of the pipe; engaging said injection pipe in the interior of the pile while positioning the injection valve means into said holes drilled in the pile; and welding said valve means to the wall of the pile from the exterior of the pile.