The M25 is an orbital road in South East England. It surrounds London and plays a pivotal role in the Highways England network. A vital route for freight, commuter and tourist traffic, it connects the many radial motorways and trunk roads serving London and provides a bypass for through traffic. An upgrade for the M25 was proposed to widen the motorway to four lanes between junctions 16 and 23.
The upgrade required extensive lengths of sheet piled retaining walls set in chalk to form the new boundary of the widened motorway. We conducted a value engineering review of these retaining walls, leveraging our extensive expertise in assessing the nature of the chalk, the derived design parameters, design methodologies and pile installation techniques.
The M25 upgrade aimed to reduce congestion and to improve reliability, safety and driver information by widening the motorway to four lanes for a section of the motorway. Due to the scale and construction programme of this project, time and cost savings were of critical importance and our value engineering review identified significant savings of both cost and time for our client.