Woodburn Engineering Ltd of Carrickfergus won the tender to Design, Fabricate and Install a new bridge across the river Mersey. As part of the enabling works for the £600M Merseylink project this bridge was essential to allow construction traffic access to and from site.
Critical to the design was the strength to withstand consistent heavy dynamic mobile machinery loads and the ability to lift allowing shipping to pass underneath when required.
With Woodburn’s 35 years’ experience in this field it was decided to design and fabricate a hydraulically operated steel Bascule Type Counter Balanced Lifting Bridge. The elevating part of the bridge has a span of 14M and 9M width. Total weight is 150Tonnes including the counterbalance ballast. Pivoting on six 100mm diameter steel trunnions, hydraulic power is delivered by a diesel power pack via flexible hoses to two 70 Tonne capacity Rams. At full lift of 67 degrees and assisted by the counterbalance ballast the centre of gravity transits the vertical pivot line making the bridge stable in the upright position.