Abstract: The invention relates to a cutter for working the soil, comprising a cutting frame, at least two cutting wheels that are supported on the cutting frame in a rotatably drivable manner about parallel axes of rotation, and an adjusting device, by means of which the centre distance between the parallel axes of rotation of the cutting wheels can be adjusted. In accordance with the invention the adjusting device includes a knee-lever mechanism. The invention further relates to a method for working the soil.

Abstract: The invention relates to a soil working method, in which a soil working device suspended on at least one supporting cable is lowered by a supporting device and introduced into the ground and subsequently the soil working device is raised from the ground by means of the supporting cable and in addition to the supporting device a holding frame is provided and the supporting cable is connected to said holding frame. The invention also relates to a soil working apparatus.

Abstract: The invention relates to a method and a test setup for determining the bearing behaviour of displacement piles. The displacement piles are produced by making a hole using a displacement head and subsequently filling the hole with a hardenable suspension, whilst leaving the displacement head in the hole. The resulting test pile is subject to the action of a test load using a loading device and the bearing behaviour is measured by a measuring device. An efficient test performance results from the fact that the displacement head is introduced into the ground by means of a metallic pile string, which forms part of the test pile.

Abstract: The invention relates to a method for sinking a borehole in the ground, in which a wet boring tool with a removal area for producing or advancing a borehole is used, the borehole is at least partly filled with a fluid and in the borehole is formed a filling area and the removal area is at least partly washed round by a fluid flow, which conveys the bore smalls produced at the removal area to a collecting container located in the borehole. The method according to the invention is characterized in that the wet boring tool has a pumping mechanism through which fluid from the filling area is made to flow and conveys bore smalls produced into the collecting container. The invention also relates to a wet boring tool and to a boring plant.

Abstract: The invention relates to a trench wall cutter with a cutting frame and a gear shield attached thereto. There is at least one cutting wheel positioned to turn on the opposite shield sides, and on it roller-shaped excavation tools distributed over the periphery are pivotally mounted. When the cutting wheel is rotating the tools form a cutting wheel cutting surface which runs essentially axially parallel to the axis of rotation of the cutting wheel. To accommodate horizontal forces, at least one additional roller is pivotally mounted on each cutting wheel, the axis of the additional roller being directed substantially radially with respect to the axis of rotation of the cutting wheel. One jacket surface of the roller on the radial face side of the cutting wheel away from the gear shield projects in the direction of the axis of rotation of the-cutting wheel.