CASE HISTORY UK / CH /BR/ Rev: 01, Nov 2018 HARBOUR BELFAST, N. BASAL REINFORCEMENT/SOIL STABILISATION Product: Paralink & Macgrid EG S Problem: The construction of a 480m long new quay structure and deep water berth located in the Port of Belfast was required a heavy use of geosynthetics. Ground conditions at a 50 acre wasteland site at were so poor that a major programme of stabilisation and improvement was required to allow the construction of a £50m trans-shipment and storage facility required to support the offshore wind industry. The riverside site which is next to Belfast’s George Best Airport and close to the City’s Quarter is the largest in the Harbour’s 400 year history. The project was part of a joint venture between Dong Energy and Scottish Power Renewables to support the construction of the West of Duddon off shore wind farm. Stabilisation and strengthening of the upper ground formations was needed as the facility was to be used for the off lading storage and assembly of huge wind turbine components. Large tracked cranes were be used to move Computer generated images of the developement equipment and materials about the site and at full capacity imposed extreme loads on the surface. The quay wall was constructed using a combi wall of 1600mm diam. 32m long tubes and 22mm sheet piles tied back and anchor beam supported on 376no. 30m long raking tubes. The 17,000sqm quay slab was supported also by 780no. 750mm dia CFA piles.

Solution: The works included dregging of the new berth and approaches. This involved the disposal of 500,000m3 of material to sea with treatment and disposal of some contaminated material to land. Behind the new quay, there is 50acres of hinterland to receive of heavy duty unbound pavement involving the placement of more 900,000sqm of geosynthetics and import of circa 1,000,000 tonnes of aggregate. With this in mind, engineers devised a scheme which involved surface build up of up to 2m depth in places using a combination of site won fill and over 250,000 tonnes of imported stone. This was placed in layers over an array of Maccaferri Paralink, basal reinforcement high strengh geogrid Paralink laid using a spreader beam approximately 1.3m below the finished surface.

Over 400,000 sqm of Paralink high strengh geogrid were used and placed in two layers set at 90 degrees to achieve maximum reinforcement of the unbound granular layers, mitigating the differential settlement across the quay slab.

Client: BELFAST HARBOUR AUTHORITIES, DONG ENERGY and SCOTTISH POWER RENEWABLES Main contractor: FARRANS CONSTRUCTION Designer: DORAN CONSULTING Products used: BBA PARALINK 1350 (400,000sqm) MACGRID EG40S (+200,000sqm) Paralink 1350 laid in 2012 Date of construction 2011-2012 Typical section

Paralink 1350 laid in 2012 Filling granular material placed over paralink

Macgrid laid on the upper layers of the pavement Granular fill material placed over Macgrid

The heavy wind farm posts and heavy cranes were placed over the reinforced pavement

Heavy crane running over the reinforced Paralink pavement © Maccaferri Ltd. All rights reserved. Maccaferri will enforce Copyright. enforce will rightsMaccaferri ©Maccaferri All reserved. Ltd.

Maccaferri Ltd: Specialist areas: Building 168, Harwell Campus, Didcot, OX11 0QT Sales: E: [email protected] T: (+44) 1865 770555 Technical: E: [email protected] Rep of Ireland: Construction: E: [email protected] T: (+353) 18851662 www.geostrong.net www.maccaferri.com/uk