Interlock Sealant
A combination of a well designed and manufactured sheet pile interlock and a properly applied sealant can virtually eliminate any fluid leakage through the sheet piles, even at high hydrostatic pressures. ESC offers a range of time proven interlock sealants that can be used for hot rolled, cold formed and cold rolled sheet piles in various conditions from tropical to arctic. They are especially effective for cofferdams and marine applications.
Al Jeer Fishing Harbour, UAE
ESC proposed an sheet pile with tieback anchor wall design for the construction of a quay wall for Al Jeer Fishing Harbour in the United Arab Emirates. ESC's design provided the owner, which was the RAK government, with a cost-saving solution that could be constructed faster and ell within project budgets. ESC also completed full manufacture of its unique wide U profile sheet piles.
Introduction
The Government of Ras Al Khaimah needed to improve their harbour and berthing facilities for the local fishing fleets. The decision was made to construct a shallow water quay wall in the Al Jeer Harbour. The requirement was for a permanent quay wall with a dredge depth of -8.0 for fishing vessels. Durability was for 50 years. All designs were to be as per the British Standards.
The Port Authorities considered several options, including suspended decks and concrete block walls, however due to economics and timing, ESC’s sheet pile wall solution with tie rods won the contract.
ESC carried out the alternative design calculations on behalf of the Contractor (Athena SA) and submitted them for approval to the Client (RAK Government) and their Consultant (Gibb Ltd). All relevant drawings and engineering detailing was provided by ESC for this project. Once approval was received the manufacturing was carried out in the ESC factory for delivery to the site.
As always, ESC personnel were on site to assist Athena SA during the beginning of the installation process. Several recommendations were made regarding piling guides and handling processes. ESC provided efficient Dawson Lifting Shackles that helped increase the productivity of the installation, while ensuring maximum safety during the process.
Soil Conditions
The existing seabed was between approximately -2.0 EL to +1.0 EL in the vicinity of the proposed wall. Subsequent filling activity has reclaimed the area to approximately +3.0 EL. Fill material is dense to very dense sandy gravel with cobbles and boulders.
The original seabed is a layer of medium dense to very dense silty sand, overlying a medium dense to very dense silty gravel layer with sandstone bands up to 8.0m thick.
Below the gravel layer are pockets of medium dense to dense sands, overlying a very dense sand layer with sandstone bands at approximately -13.0EL.
Corrosion Protection Coating
The specified coating for the sheet piles is for sand blasting to SA2.5 followed by 50 micron of primer and then 400 micron of coal tar epoxy paint. The coating is to be applied to the entire front surface and two metres of the back surface of the Main Wall piles only.
Installation
Installation was done by pitching the sheet piles in a piling frame and driving to refusal with an ICE 815 vibro hammer. Piles were then driven to the final required level using an IHC S90 hydraulic hammer, together with a pile helmet.