THE longest bridge ever built by Groundforce Bridge has helped civil engineers APL Construction span an 11m watercourse and flood area in Lesmahagow, Lanarkshire.
The bridge comprised two 17.6m x 3.5m structures laid end to end and was complemented by a single 17.6m x 3.5m bridge to give APL two crossings over the watercourse for vehicles up to 60 tonnes including metal-tracked excavators.
Totalling 57 tonnes in weight, the two bridges were built in just over a month and will be needed by APL for at least six months.
APL had contacted Groundforce Bridge to discuss what options were available to give a maximum clear span of 15.6m over the watercourse. Project co-ordinator Chris Stevenson carried out a pre-installation site visit to devise the best plan. He found the vegetation area surrounding the watercourse obstructed any lifting access and the site was extremely difficult terrain for delivery and installation.
The solution was the two 17.6m x 3.5m bridges laid end to end with 14 deck plates to span 35.2m, with concrete gabion basket abutments designed and installed by APL at the centre joint point of the two bridges.
The first half of the 35.2m bridge was able to be installed using a HIAB but the second half required a 250-tonne mobile crane with further reach. Groundforce Bridge was able to install the third 17.6m x 3.5m bridge with seven deck plates using the HIAB to gain access to its location by driving over the 35.2m bridge to the lifting area.
The bridges were delivered to site using two wagons, an articulated steerable extended trailer and the HIAB. As well as the abutments, APL groundworks included de-vegetation and preparing the stoned access road, crane pads and stone ramps.
Groundforce Bridge director Terry Mead said, “This was one of the most challenging projects we have undertaken since the bridge division was formed in 2012. It has been a fantastic project to work on in Scotland and has been a great team effort all round.
“Once the plan had been put in place, steel ordered and bridges fabricated, all three bridges were delivered and installed in the time scale set by our client.”
