Abstract: Novel subsea excavation apparatus and methods that exert force between a subsea anchor point and an excavator using a subsea actuator. In some examples the subsea actuator is attached to an anchor point on the seabed and the excavator directly. In other examples, a guide frame is anchored to the seabed to provide anchor points fixed relative to the seabed and the subsea actuators are attached to the guide frame and the excavator. In further examples, the subsea actuators can be attached to the excavator through a carrier frame or other excavator guides rather than directly to the excavator.

Abstract: A dredge propulsion system mounted on the same boom as the cutter head. The propulsion system has one or more augers which can be operated individually to maneuver the dredge. In the preferred embodiment a pair of augers are mounted parallel to one another on a subframe which is connected to the boom of the cutter head. The subframe comprises a first member pivotally attached to the boom. Each auger is carried by a three bar linkage mounted to the first member.

Abstract: In one embodiment of the present invention, an apparatus is disclosed for accommodating a substantially vertical spud of a dredging vessel with a longitudinal direction, including a spud carriage which is mounted for limited rotation around a horizontal transverse axis, wherein at least a first and a second spring device is arranged under bias between vessel and spud in the longitudinal direction for the purpose of absorbing a moment on the spud carriage, which first and second spring devices compensate each other in the non-loaded situation of the spud; and at least one spring device is provided with a spring force limiting device for limiting the tension in the spring element from a determined maximum moment on the spud carriage.

Abstract: This invention relates to a bucket (12) for a mechanical shovel (10). The bucket has a hollow body (16) provided with an inlet (14) for receiving material into its interior and an outlet (15) for discharging material therefrom. A door (18) is secured to the body and is movable between a closed condition in which it closes the outlet, and an open condition in which it permits discharge under gravity of material from the bucket. A buffering device in the form of a working fluid containing telescopically extensible and retractable piston-and-cylinder assembly (22) is operatively connected between the body and the door of the bucket for buffering movement of the door relative to the body.

Abstract: In embodiments of the invention, a dredging head assembly uses vacuum only, or a combination of vacuum and flexible PVC tines, rather than the harsh digging and/or scraping features of conventional dredging equipment. Embodiments of the invention also provide a dredging head assembly that may be used in very shallow water. An embodiment of the invention includes a hose and wand to enable vacuuming around obstacles. One variant of the dredging head assembly is adapted for skimming floating debris from the surface of a body of water.

Abstract: In one embodiment of the present invention, an apparatus is disclosed for accommodating a substantially vertical spud of a dredging vessel with a longitudinal direction, including a spud carriage which is mounted for limited rotation around a horizontal transverse axis, wherein at least a first and a second spring device is arranged under bias between vessel and spud in the longitudinal direction for the purpose of absorbing a moment on the spud carriage, which first and second spring devices compensate each other in the non-loaded situation of the spud; and at least one spring device is provided with a spring force limiting device for limiting the tension in the spring element from a determined maximum moment on the spud carriage.

Abstract: A marine backhoe dredge having a counterbalancing system that increases the hoisting capacity and hoisting speed of the backhoe. The device includes a backhoe mounted on a vessel and a counterbalancing system that includes an adjustable support structure, one or more cables operatively associated with the support structure and backhoe, and connected to a counterbalance such as a counterweight or a winch.

Abstract: The apparatuses for improving the permeability of a fluid containment basin having a plurality of ridges and furrows in the bottom of the basin are configured to disturb sediment that has settled on the ridges so as to place the sediment back into suspension. In one configuration, the apparatus comprises a tool support frame adapted to support one or more ridge cleaning tools on top of the ridges. The tools include dragging, discing and grinding tools. The discing tool is configured with a flexible axle to allow the tool to move in response to changes in the contour of the ridge. In another configuration, a boat or other device is moved across the basin above the ridges to cause wave energy from the boat's propellor to disturb the sediment on the ridges. The tool support frame with one or more ridge cleaning tools can be pulled behind the boat.

Abstract: An aquatic weeding device is provided for removing aquatic vegetation from a body of water and transporting the vegetation to a desired location. The weeder includes at least one weeding element connected with respect to a vessel for collecting aquatic vegetation, an extendable and retractable weed transporter positioned on the vessel for transporting the cut vegetation to a desired location, and a weed transferor positioned on the vessel for transferring the collected vegetation from the weeding element to the weed transporter.

Abstract: A system and method removes contaminated sediments during mechanical dredging operations, while maintaining a predetermined low moisture content of the contaminated sediments. The system uses a specially designed positive pressure controlled enclosure or enclosed excavator that houses a mechanical bucket and prevents ambient water from contacting the sediment during the excavation process.

Abstract: A marine system and method is presented for collecting, containerizing, and transporting contaminated sediments collected during dredging operations in the marine environment. The system makes use of a specially designed marine-based platform to process and distribute the sediments into containers located on a separate sediment transport vessel. The system described bypasses the need for on-shore sediment processing facilities.

Abstract: A method is described for containing dispersed particulate or soluble matter during contaminated sediment remediation operations in the marine environment. The preferred method comprises the use of a specially designed marine vessel that establishes a negative differential pressure gradient between a defined remediation control zone and the external ambient water environment, thereby preventing the release of contaminants dispersed during the remediation process. The preferred method also includes the use of marine vessels to remove contaminants contained within said control zone and to provide for the management of solids collected in the process.

Abstract: A method is described for removing sediments during dredging operations to minimize the release of contaminants at marine locations containing sediments that are deemed contaminated and require removal. The preferred method comprises the use of a specially designed marine vessel that establishes a negative differential pressure gradient between a dredge control zone and the external ambient water environment, thereby preventing the release of contaminants dispersed during the dredge process into the ambient water environment. The preferred method also includes the use of marine vessels to remove contaminants contained within said control zone and to provide for the management of solids collected in the process.

Abstract: A method for installing a pile anchor into the sea floor that enhances the holding capacity of the pile anchor. The pile anchor is installed at an inclined angle with respect to the sea floor, with the top of the anchor inclined in a direction opposite the lateral load applied to the anchor.

Abstract: A hand-held tool for a diver has a hollow tube to vent pressurized gas from an interconnected source through an opening in the tube. The vented pressurized gas aerates material of a seabed, and an anchoring system disposed adjacent to the tube is effortlessly inserted in the aerated material by a single diver. The hand-held tool permits an improved method of inserting the anchoring system as compared to the time consuming, strenuous, and noisy hammering procedure that usually requires more than one diver to successfully embed an anchor in the seabed. Different sources of pressurized gas for aerating the material may include a portable gas cylinder, diver's air tank, or hose from a remote source, such as a compressor. Quick-change connectors can be used to quickly and easily connect and disconnect components to supply more gas or add different components that will help insert different anchoring systems.

Abstract: A system and method removes contaminated sediments during dredging operations to minimize the dispersion of particulate matter that normally occurs during conventional mechanical or hydraulic dredging operations. The system uses a specially designed pressure controlled enclosure or enclosed excavator that houses a mechanical bucket. The enclosure is designed to capture suspended particles that are dispersed into the water column during the mechanical dredging process. The system also includes the use of a self-contained membrane filtration treatment vessel to remove fine particulate matter from dredge drainage waters collected in the process.

Abstract: A dredging apparatus comprising a body mounting thruster to direct, in use, a wash of water downwards towards an area of sea bed or the like, connection device to connect the dredging apparatus to a support vessel above the sea bed, said connection device including attitude adjusted to selectively adjust the attitude of the dredging apparatus in a side to side (roll) orientation.

Abstract: In a method of and apparatus for anchor installation, a plate anchor is mounted at the bottom of a suction follower comprising a hollow cylinder having an open lower insertion end and a closable upper suspension end. The suction follower and the anchor secured thereto are engaged with the sea floor, whereupon water is pumped out of the suction follower causing the suction follower and the anchor to penetrate into the sea floor to a predetermined depth. The anchor is then disengaged from the suction follower, whereupon water is pumped into the suction follower to disengage the suction follower from the sea floor for recovery to the surface, leaving the anchor embedded in the sea floor. The plate anchor may comprise first and second plate members, the second plate member pivoting relative to the first plate member to prevent upward movement of the anchor.

Abstract: A bidirectional dredge provides active dredging on both forward and reverse passes across an area being dredged. The dredge includes a pivot turning mechanism that allows a turnaround of the dredge, allowing each pass to start at the terminating point of the previous pass. The dredge is driven by a winch attached to an overhead cable strung between the perimeter of the dredging area. The winch is mounted on a pivot mechanism which is operative to rotate the dredge at each end of a dredging pass. The pivot mechanism includes a pair of plates which rotate, a lower plate being attached to the dredge, and an upper plate attached to the winch. At the end of each pass, the pivot unit is activated and the dredge rotated. Following rotation, the dredge is now facing forward toward the distal end of the dredging area, and ready to effect an active dredging pass in the opposite direction, thereby utilizing every pass over the area for active dredging.

Abstract: In a method of and apparatus for anchor installation, a plate anchor is mounted at the bottom of a suction follower comprising a hollow cylinder having an open lower insertion end and a closable upper suspension end. The suction follower and the anchor secured thereto are engaged with the sea floor, whereupon water is pumped out of the suction follower causing the suction follower and the anchor to penetrate into the sea floor to a predetermined depth. The anchor is then disengaged from the suction follower, whereupon water is pumped into the suction follower to disengage the suction follower from the sea floor for recovery to the surface, leaving the anchor embedded in the sea floor.

Abstract: A dredge including a V-shaped or U-shaped pontoon having a first leg and a second leg. The legs have effective longitudinal axes that diverge from one another by an angle of no more than 180.degree.. Spuds or similar anchoring devices are connected to each of the respective pontoon legs by slides that allow the pontoon to be advanced relative to a substrate to which the spuds are anchored. A bucket wheel is suspended from the pontoon by a dredge ladder. A slewing device is provided to cause the dredge ladder, and the bucket wheel attached to it, to be slewed from side to side relative to the legs of the pontoon, about a substantially vertical axis.

Abstract: A carry scraper ship having a tug lighter for towing, a device for scraping and lifting earth and sand accumulated on ground under water, a bucket conveyor for conveying earth and sand scraped and lifted from ground under water to an atmospheric environment above water, a belt conveyor lighter for discharging earth and sand conveyed from under water to the atmospheric environment onto earth carriers, and a structure for linking the tug lighter, the device for scraping and lifting, the bucket conveyor and the belt conveyor light together in operative relationship.

Abstract: A method of removing objects from the bottom of a body of water around a well head includes a vessel spooling out a link-chain or a cable-net from a winch located on the vessel, with the opposite end of the link-chain or cable-net attached to a swivel assembly placed over a vertical pile that marks the well head site. The link-chain or cable-net is laid along a path defined by a radius and a portion of the circumference extending from that radius of a circle of predetermined diameter. The vessel then lowers spuds to establish a rigid position and the link-chain or cable-net is winched in. Objects on the bottom of the body of water are either picked up by the net, or obstruct the link-chain or cable-net and can be marked for retrieval.