CONTRACTORS WIDENING the A3 Northway bypass in Portadown, Northern Ireland, have chosen segmental retaining walls from Anchor Wall Systems to help speed the construction process and keep traffic disruption to a minimum during the 26 week contract period.
Anchor Vertica Walling units manufactured by Northern Irish construction materials specialist Acheson & Glover have been selected for the job.
The original A3 Northway passed through a heavily built up area of Portadown, with only the minimum area of land available for widening.
Working within these constraints meant that new retaining wall structures were needed to support the 3m to 4m high elevated carriageways, roundabouts and filter roads for the enhanced network. The £1.15M scheme was designed by consultant Maccaferri with contractor Gibson.
Complex internal and external curves also meant that traditional reinforced concrete retaining walls would be too costly because of the insitu concrete foundations, elaborate shuttering and many separate pours that would have been required.
The Anchor Vertica walling used at Portadown is a dry built, segmental retaining wall system made up of concrete facing blocks that work together with geogrids and compacted back- l to form an engineered retaining wall.
The Anchor system is installed by hand and does not require concrete foundations.