Abstract: When compacting soil a vibration mass bearing on the ground is caused to vibrate, wherein the vibration process is controlled in dependence on the behaviour of the mass spring system, part of which being constituted by the soil. Tests have shown that in comparison with fall weights soil can be compacted up to the same extent in a shorter period of time or can be compacted to a greater extent in a same period of time.

Abstract: In a dredged soil conveying vessel comprising a hold which is open on the bottom side and which is enclosed between two pivotally interconnected ship's halves, each of which has floating power and joining one another along their bottom rims in the closed state, in order to provide many efficient modes of discharge of the dredged soil conveying vessel, one ship's half is provided near the bottom of the hold with a draining suction channel communicating with the hold through an opening that can be closed, said channel communicating with a pump connected with a slush outlet conduit and inside the hold of the dredged soil conveying vessel a plurality of water supplies are directed along the walls.

Abstract: A watertight seal (1) between two adjoining channel-shaped concrete elements (2) has an elastic sealing strip (3) sandwiched between a socket (5) of one concrete element (2) enveloped by the socket (5). The sealing strip (3) is recessed and has a transverse profile such, that when the socket is slid over the wedge (7), material (12) of the sealing strip (3) shifts in a direction contrary to movement of the socket in order to prevent damage of the sealing strip.

Abstract: When sucking ground material through a lying, elongated suction slot moved ver the ground, the water stream for suctioning this ground material is adjusted in dependence upon the types of ground material to be fluidized.

Abstract: Method and device for safeguarding hydraulic transport of a suspension of edging spoil and water by supplementing a dosed water amount onto the suction side of the pump, whereas as much and as long as possible suction power is maintained in the suction duct for feeding much material to be transported and little water into the suction duct.

Abstract: An artificial island is constructed by depositing material such as sand, y or the like on the building site on the bottom and by providing inhibiting means formed by branched, relatively spaced elements positioned on the building site, to reduce the rate of effluence of the material such as sand, clay or the like along the sea bottom.

Abstract: The method of dredging accurately to a desired profile contour with a cutting dredger involves the operation of a cutting assembly, the cutting tools of which describe a predetermined cutting envelope, and swinging the cutting assembly while the dredger is anchored at a known point. The known point is established by means of land-based radio beacons and an aerial aboard the dredger, the dredger being anchored at the known point while the longitudinal axis of the dredger is aligned or substantially aligned with the longitudinal axis of the desired profile contour. As the dredger is swung with the cutting tools engaging the material to be dredged, the location of geometric points of the dredger assembly are repetitively calculated with respect to the coordinate system of the desired profile contour, taking into account various angular relationships between and among such points and by also taking into account motions of the dredger as affected by wave and/or tide actions.

Abstract: A device for separating a mixture of, for example, oil and water consists of a number of elements treating the mixture in stages, said elements being arranged in overlying position in order to manufacture a compact device.

Abstract: A transport conduit comprises a stone catcher housing having a grid basket arranged in it. The stones sticking in the meshes of the grid basket are flushed out of it or they are getting loosened when removing the basket from the housing.

Abstract: In a method of loading a suction dredger in which a suspension of sand and ater is pumped into the hold an effluent device is intermittently passed to lower and lower levels in dependence upon the weight of the load in the hold to an extent such that the suction dredger remains loaded substantially up to its maximum permissible carrying capacity.

Abstract: When loading a loading space 2 of a dredging vessel 1 with sand the head er 5 is removed from the loading space 2 by means of more than one siphon 12 and is conducted away into the water stream 26 moving around the vessel 1. This head water can be polluted with much sludge or another pollutant.In order to reduce pollution of the environment with the aid of effluent means which are not very expensive and which can be easily adjusted, said effluent means comprises in accordance with the invention a tubular sheath 24, inside which is telescopically arranged a level-adjustable common outlet conduit 21 which can be withdrawn into said tubular sheath and be brought out thereof to a considerable distance below the vessel 1 respectively, and which is connected with coupled conduits 16, 19, 18 of more than one siphon 12.

Abstract: Hard ground beneath a water surface is controllably cut away by a device ch includes a buoyant body having a work support depending therefrom and forced against the hard ground so as partially to support the weight of the body. A cutter assembly is releasably clamped to the work support and the clamp has arms connecting it to a short, rigid carrier which mounts a rotatable cutter head at one end. The arms allow the carrier to swing about a horizontal axis and a vertical axis and hydraulic motors are provided to sweep the carrier about such axes in controlled fashion. A winch on the body allows the carrier to be clamped at desired vertical positions on the work support.

Abstract: A separating device for separating by gravitational segregation a mixture of a carrier liquid and substances suspended therein comprises a separator arranged in a separator housing and having parallel, sloping plates, a stilling space arranged in front of said separator and having on the top side a first collecting space intended for light-weight substances, a feeding space near the inlet side of the separator, a second collecting space near the top wall and a third collecting space arranged behind the separator.The separator housing is constructed as a pressure vessel and the first and second collecting spaces communicate with one another through a conduit, the flow resistance of which exceeds that of the separator.

Abstract: In order to accurately control the cutter head of a cutter head suction dredger anchored by means of ropes, the tension in at least one of the two longitudinal ropes is measured and the winch of at least one of the two longitudinal ropes is actuated in dependence upon the tension measured in the one longitudinal rope.

Abstract: In a method of loading the hold of a suction dredger vessel, in which a sension of sand and water is pumped into the hold during loading which is carried out in a first stage and a subsequent second stage for avoiding that a siphon effect is not possible and that the last quantity of water cannot be replaced by a sand-water mixture, the effluent means are kept, after the suspension level in the hold has reached the external water level, under the action of a suction pump for lowering the suspension level to below the external water level.

Abstract: A method for loosening stony soil by means of a rotating cutting head fastened to the rear of a tractor and having cutting members to be drawn through the soil and being mounted according to a helical line.Stony soil can be readily loosened to the desired depth because the cutting head can be kept at an acute angle to the direction of movement. So the cutting head is drawn in a stable manner in the direction to the tractor against the stone surface concerned and penetrates the stony soil like a plough, the soil above the cutting head being torn up upwardly.

Abstract: When breaking up lumps of stone from a subaqueous stony ground, the lumps are loosened by means of at least one chisel inserted into the ground and being moved along the ground surface. In order to break up lumps of stone by low power and to main a predetermined size of the loosened lumps of stone suitable for being lifted by a suction dredger system, the structure of the top layer of the stony ground is disturbed by inserting displacers from above into the ground at places distributed over the ground surface.

Abstract: Method of separating a mixture of a carrier medium and at least one substance insoluble therein, for example, water and oil or gas and soot, in which the mixture is separated in three steps, i.e. a first step in which the mixture is passed for coalescence of the substance through a first packet of moving filter material, a second step in which the substance coalesced segregates from the mixture by gravity and a third step in which the remainder of the substance and the other packet of filter material is filtered out.

Abstract: A device for separating water from light-weight and/or heavy substances contained therein. The separation takes place in a packet of parallel separation channels.In order to prevent that too many light-weight substances enter the upper separation channels, the flow into the upper separation channels is throttled.Also the lower separation channels may be throttled for restricting the heavy substances entering therein.

Abstract: In a method of collecting light-weight substance floating on a liquid the light-weight substance is sprayed with the aid of a liquid jet into an accumulator tank in that the light-weight substance lands together with the liquid jet as a downward stream about a lower edge of the open bottom of the tank into said tank.In order to keep the liquid jet effective the disintegration of the liquid jet is prevented. To this end the liquid jet is guided above the layer of light-weight substance along a bar or similar guide means.