A device for reducing underwater sound energy and propagation, whereby the device includes at least one bubble generation unit and an air conduit for supplying pressurized air to the bubble generation unit, whereby the bubble generation unit has a fluidic oscillator for generating one or more pulsating air flows from a constant air flow, and whereby preferably the fluidic oscillator has an adjustable oscillation frequency, and a method for using such a device for reducing underwater sound propagation, whereby the air conduit and the bubble generation unit are placed underwater, whereby pressurized air is supplied to the air conduit and whereby air bubbles are generated by the bubble generation unit.

A device for reducing underwater sound has a holding device and a hydrosound damper with noise reducing elements. The device has a transport housing for transporting the hydrosound damper, a first end of the underwater sound damper being fixed to the transport housing and the transport housing being connected to a holding device via a support device has a cable winch with a support cable arranged on the transport housing and has a motor-driven drum, wherein using the support device, the transport housing is lowered from the holding device to the sea floor.

A device for reducing underwater sound has a holding device and a hydrosound damper with noise reducing elements. The device has a transport housing for transporting the hydrosound damper, a first end of the underwater sound damper being fixed to the transport housing and the transport housing being connected to a holding device via a support device has a cable winch with a support cable arranged on the transport housing and has a motor-driven drum, wherein using the support device, the transport housing is lowered from the holding device to the sea floor.

There is disclosed an acoustic barrier (40) for use in a pile driving method in which a pile (I0) is driven into the ground 60, the acoustic barrier (40) comprising: an acoustic dampening layer (42); and a magnetic element (36); wherein the acoustic barrier (40) is arranged to be at least partly wrapped around an axial portion of the pile (I0) so that the acoustic dampening layer (42) at least partly surrounds the axial portion of the pile (I0), and wherein the magnetic element (36) is arranged to releasably secure the acoustic barrier (40) to the pile (I0). There is also disclosed a pile driving method comprising wrapping the acoustic barrier (40) around an axial portion of a pile (I0), driving an axial length of the pile (I0) into the ground, and removing or repositioning the acoustic barrier (40). There is also disclosed an acoustic barrier for a pile driving hammer having a support frame which can be detachable attached to the hammer.

A noise-attenuating pile comprising a pile driving shoe, an outer tube that engages the pile driving shoe, and an inner member that extends through the outer tube and engages the pile driving shoe, wherein the pile is configured to be installed in sediment or other suitable material by driving the inner member with a pile driver, without directly impacting the outer tube, such that the radial outer tube is substantially insulated from the radial expansion waves generated by the pile driver impacting the inner member. In some piles, one of the inner member and the outer tube are removable after installation. In some piles, a seal is provided in a lower end of the channel defined between the inner member and the outer tube, which may be biodegradable, or may be an inflatable bladder, for example.

A device for and methods of reducing sound vibrations in a liquid resulting from a sound source arranged below the liquid level of a body of water are disclosed. The device includes an elongate tube which can be arranged over the sound source, the tube comprising an outer wall and inner wall with an intermediate space between the inner and outer wall.

The invention relates to an apparatus for noise attenuation in an impact pile driving device wherein the apparatus comprises a pile guide being attachable to the lower end of a hammer of an impact pile driving device. The apparatus according to the invention comprises compressing arrangement in connection with the pile guide having at least one compressing element and mechanical, hydraulic or pneumatic compressing means for compressing a pile fitted in to the pile guide transversally by means the at least one compressing element. The invention relates also an impact pile driving device and a method for noise attenuation in an impact pile driving device.

A device for reducing underwater sound has a holding device and a hydrosound damper with noise reducing elements. The device has a transport housing for transporting the hydrosound damper, a first end of the underwater sound damper being fixed to the transport housing and the transport housing being connected to a holding device via a support device has a cable winch with a support cable arranged on the transport housing and has a motor-driven drum, wherein using the support device, the transport housing is lowered from the holding device to the sea floor.

A pile-driver assembly for driving a pile into the ground, preferably off-shore, and a method of driving a pile into the ground using the pile-driver assembly is disclosed. The assembly includes a casing defining a chamber, the chamber being configured to house a fluid, the chamber comprising a channel extending at least partially therethrough. The assembly further includes a positioning element configured to position the casing at or on the pile, wherein at least a portion of the positioning element is positioned between the chamber and the pile, wherein the positioning element comprises a guide element, configured to extend at least partially through the channel of the chamber. The assembly further includes actuating means, wherein actuation of the actuating means displaces the chamber relative to the positioning element, such that the chamber moves away from the pile, and wherein the actuating means is configured to release the chamber for displacement towards the pile such that a force is exerted by the chamber on the positioning member, to controllably drive the pile into the ground.

A manufacturing method of a noise reduction module that is used underwater to attenuate low-frequency noise comprises steps of substrate preparation, functional layer fabrication, and encapsulation. The steps are performed by substrate preparation of functional layers of rubber and/or polyurethane, mixing sound-absorbing materials in the substrate material to constitute the sound-absorbing layer, and constituting the encapsulation layer by the substrate material, externally encapsulating the sound-absorbing layer by the encapsulation layer, in order to make into the noise reduction module in a modular structure, which can absorb the incoming sound wave energy by the sound-absorbing layer. The noise reduction screen can be composed of a plurality of the noise reduction modules.