Construction on the M25
Client: Balfour Beatty Major Projects Ltd for the Highways Agency and Heathrow Airport Ltd
Value of contract: £11 million
The McArdle Group completed this design and build project for the M25 (Junction 12 to 15) and Heathrow Terminal 5 (T5).
The civil engineering project involved widening the existing three and four-lane motorway to four, five or six lanes in each direction, and Stage 2 construction of the spur road into T5.
Principal activities comprised:
- Early contractor involvement to quantify cut/fill volumes and provide advice on engineering strategy
- Bulk earthworks
- Recycling of site won and locally sourced demolition material to provide capping, sub-base and structural backfill
- Road construction
- Formation of landscape and environmental features including resoiling and grass seeding to all soft surfaces
- Formation of pile platforms and foundations for VCB and surface water channel in the verges and central reserve
- Structural backfill to bridge abutments including forming back of wall drainage
- Infill of part of an existing lake at Jn 14 clockwise off-slip road to construct the realigned slip road
The contract was an NEC option D (Bulk Earthworks and Road Construction) and NEC option B (Recycling and Materials Supply).
