Project of the Year by a Specialist Contractor (subcontract from £1m to £5m): winner

Winner: Geobear – Shugborough Tunnel Shaft Void Filling & Tunnel Lining

The Shugborough Tunnel, carrying the West Coast Mainline, was built in 1846-47 and is located beneath a National Trust property featuring extensive gardens in Staffordshire.

“The scheme epitomised an exemplar delivery of a complex engineering challenge and the project team should be rightfully proud of their achievements”

Judges’ comment

The methods used in its original Victorian-era construction had resulted in voids appearing along the tunnel as deterioration occurred. These needed careful and accurate filling. Using traditional dense, wet grout would have increased the load on the tunnel, potentially resulting in catastrophic damage.

Working for client Network Rail, Geobear designed a lightweight, low-carbon, fast-curing geopolymer solution to fill the void around the lining beneath each shaft and one metre inside the shaft, with another geopolymer used to fill the rest of the shafts.

Work was delivered across 50 night-time possessions on the busy railway line.

Judges were impressed by the team’s work with Network Rail to devise such an innovative solution and deliver it in a constrained environment within budget and to the satisfaction of all stakeholders, which also included Story Contracting and COWI.

The panel said: “The Shugborough Tunnel project epitomises an exemplar delivery of a complex engineering challenge and the project team should be rightfully proud of their achievements in this respect. Geobear is a very worthy winner of this award.”

Highly commended: David Jameson Roofing Services – Thales Re-Roofing Project

The project involved removing and replacing a 4,000 square-metre roof in a working factory that could not be shut down at any time, with the project team only allowed to cordon off one bay at a time.

It required lengthy planning and an intelligent approach to sequencing of works to carry out the job – with tasks including safely removing a large expanse of asbestos.