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The longest beams in UK & Ireland Banagher Precast Concrete break records with their 50 metre concrete beams
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anagher Precast Concrete always push boundaries when it comes to precast solutions for rail and highways and in recent months they became the first precaster in the UK or Ireland to manufacture prestressed concrete W-beams measuring 50 metres.
Laney River Bridge The N22 Ballyvourney to Macroom project in County Cork includes for the construction of 22 kilometres of dual carriageway and is one of the largest infrastructure projects underway in Ireland at the moment. The £240 million project includes the construction of 130 structures including crossings over the Sullane, Laney, and Bohill rivers – each one a challenge and each one a record breaking structure, the Macroom bypass project is engineering at its finest. Originally designed in steel due to the 50-metre span, structure 26 Laney River Bridge is now the longest single span prestressed concrete bridge in the UK or Ireland. This significant achievement was reached by the main contractor, Jons Civil Engineering/John Cradock Ltd JV (CJV) who safely installed the seven Banagher W19 beams, each measuring 50 metres long, 2.5 metres high and weighed an impressive 155 tonnes in December. Logistics Manufacturing and delivering the beams to site was a major logistical exercise. Banagher’s Senior Engineer, Eamon Stack, who developed the now industry-standard W beams back in 2005, worked very closely with Barry Transportation, TYPSA and the client Jons Cradock JV on the beam design, over several months the calculations and designs came together until Transport Infrastructure Ireland (TII) was comfortable with the proposed beam performance. The beams were cast on one of Banagher’s 200-metre-long W bridge beam lines, using on-site gantry cranes to lift the 155-tonne beams. Transport of the beams required police-escorted overnight journeys, the 190-kilometre journey which usually takes 2.5 hours took over twelve hours with these abnormal loads. Transported in pairs the beams travelled the first 40 kilometres of their journey on the first night, leaving Banagher late each evening in order to minimise disruption to other road users and the local communities. Manoeuvring prestressed beams the same length as Olympic swimming pools through the neighbouring country town was one of the biggest challenges. Given their extreme length the beams had to be carefully navigated by the bogey team through a ‘pinch point’ in the town centre under the scrutiny of the crowds that had gathered. With sufficient preparation and analysis this aspect of the works was delivered with minimal fuss. When the W19 beams arrived on-site they were offloaded directly onto trestles without the use of a crane. This offloading system is especially useful on this type of project where the logistics of moving 50-metre beams takes several days. Along with the added benefit of reducing craneage on-site, the trestles also allow for additional works such as the edge protection to be installed prior to lift. The beams were then lifted into place in December 2020. Rail Professional
Sullane River Bridge While the 50 metre beams stole the limelight, Banagher was also manufacturing the second-longest bridge prestressed concrete beams ever made in the UK and Ireland. Also on the N22 project the Sullane River Bridge (structure 28) now holds the title for the longest two-span prestressed concrete bridge, each of the fourteen 48.75m W-beams were successfully lifted into place in February 2021.
Longest 2-span Prestressed Concrete Bridge, 48.75-metre Banagher W beams
Recent rail projects - Whitacre footbridge Although Banagher Precast Concrete don’t specialise in architectural precast their long-standing client Story Contracting commissioned a new pedestrian bridge for Whitacre, Birmingham on behalf of Network Rail. The bridge was designed to replicate the lattice design commonly found on old steel rail footbridges. This offsite solution was cast with a NOEplast formliner to give it a high quality finish and the 2 parapets were stitched together with a second stage pour in the factory so that the unit could be installed as one complete section. Banagher also provided precast stairs and landings so the entire structure could be successfully installed in a single weekend possession in March 2021.
Lattice patterned parapet straight out of the mould
