Northamptonshire tunnel transformation project reaches key stage

L-R: Neil Perrins, Stepnell; South East Midlands Local Enterprise Partnership programme and assurance manager Judith Barker; Dr Rob Lewis OBE, managing director of Aero Research Partners and TotalSim; South East Midlands Local Enterprise Partnership programme support officer Lucinda Young.

A trailblazing project which is transforming a disused Victorian railway tunnel in Northamptonshire into a hi-tech vehicle testing facility has reached a key stage and Stepnell have now completed the retaining structures which will enable the development of the main building at the new Catesby Aero Research Facility (CARF).

Brackley-based Aero Research Partners are behind the project to create a technologically advanced facility for aerodynamic testing set to attract car industry and motorsports customers from around the world.

The remodelling of the 2.7km long 1897-built tunnel into a smooth asphalt road will deliver a unique, highly-controlled test environment allowing vehicles to reach speeds of over 100mph and enabling accurate assessment of vehicle performance, aerodynamics, noise, emissions, and cooling.

During the widening of the railway cutting, the Stepnell team used two soil-nailing rigs to reinforce the ground and build retaining walls.

The soil-nailing process involved the insertion of up to 14-metre long hollow steel nails into the sloping ground with grout injected at pressure through the nails before mesh and fixing plates were then attached to the bar ends to keep the slope face stable. The team is now working on the next phase of the project involving construction of the CARF building outside the south tunnel entrance.

Stepnell project manager Neil Perrins says: “Our team is making excellent progress on this challenging and complex construction and civil engineering project. The next phase will see us install new drainage to improve or replace the existing drainage, as well as build the two-storey steel framed CARF building within the footprint provided by the retaining structures we have created.”

The other partners working on the scheme are Roger Coy Partnership (architects); Lockhart Garratt (landscape design); David Smith Associates (civil engineers) and David Symonds Associates (civil and structural engineers). The project is going ahead with support from Daventry District Council.

As well as the tunnel and research centre, the new facility will also feature a 4.5 acre science park with offices and workshops. The project is going ahead with £4.2 million in funding from the Government’s Local Growth Fund through the South East Midlands Local Enterprise Partnership. The facility is expected to open in late 2019.