Harland and Wolff - Shipbuilding and Engineering Works

Belfast Dock
The Engineer" Jan 28 - 1998

The Dry Dock is being constructed under an arrangementconcluded by the Government.
The Belfast Harbour Commissioners and Messrs. Harland & Wolff Ltd. It will be owned and operated by the Commissioners. Ideally situated adjoining a large turning circle. The site was reclaimed from the sea many years ago and has been reserved for a dry dock by the Commissioners since the 1930's. Wartime plans to construct such a dock on the site did not materialise. If one had been built even a few years ago it would, perhaps have been much smaller than that on which work has now begun.The dock, which will be the largest in Europe is due to come into commission in approximately 3 years’ time, and should meet the needs of the Harbour and of ship-owners for many years to come.

The principal dimensions of the new Dry Dock will be:

Length 1100 feet
Entrance width 165 feet
Barrel width 167 feet
Depth of water 38 feet at Mean High
over sill Water of Spring Tides

The Dock will be provided with the most modern equipment and will afford facilities equal to those available anywhere in the world.

For handling ships into and out of the Dock speedily. Safely and economically, remotely controlled lead-in-trolleys are to be installed. Capstans will also be available to assist these operations and for other duties.

A large continuous subway behind and below the coping line of the Dock will house piped and electrical services. The latter will supply all facilities required for modern ships and repair operations.

The pumping plant which will dewater the Dock with no ship in it in about three hours is to be housed on the west side of the Dock entrance. Filling the Dock by gravity will be achieved in about one hour.
Adjacent to the pumphouse a second building will house the mechanical and electrical plant and switchgear. Over the building, modern office and mess accommodation is to be provided for the Dock operating staff.
Cranage facilities of the most modern type will be provided on both sides of the Dock.

The Dock floor will be of reinforced concrete founded on clay. The rock and other porous strata under the clay contain water under pressure. Where the rock level is close to the underside of the floor the impermeable clay layers are thin and so there will be large hydro static forces tending to lift the Structure. In these areas the floor will be anchored to the rock by high tensile steel bars.

The main Dock walls will be formed of steel piling driven into the dense boulder clays and rock. These walls will be anchored back by steel piles driven at a rake of 1 in 1 and acting in tension this technique has not been previously adopted in the U.K. as far as is known.

The steel sheet piling walls will be surmounted by a reinforced concrete relieving platform type super structure embodying the dockside services subway.

A continuous altar on the Dock face will give access to the services connection points and the flights of Dock stairs.

The Dock entrance gate is to be hinged flap type structure which will lie just above seabed level when fully opened.