CRL was appointed as the concrete repair contractor alongside VolkerLaser, operating under the principal contractor joint venture BMV, comprising BAM Nuttall, Morgan Sindall and VolkerFitzpatrick. CRL’s scope covered the northern section of the viaduct closest to Junction 1, a 0.93-mile length of deck equating to approximately 50,000 m², effectively half of the overall structure. While the repair techniques were familiar, the sheer scale of delivery was unprecedented within the UK concrete repairs sector.
Works were executed in three distinct phases to maintain two-way traffic flow on this strategic route. The southbound carriageway was addressed first, followed by the northbound carriageway and finally the central reservation. During the initial southbound phase, the four-lane carriageway was closed for 13 months, with both traffic directions managed on the northbound carriageway via a contra-flow system. This arrangement enabled CRL operatives to work two full shifts per day, six days a week, maximising productivity while maintaining network availability.
The technical repair process involved extensive hydro-demolition to remove defective concrete, supported by continuity testing to confirm reinforcement condition. Sacrificial anodes were installed to mitigate future corrosion before reinstatement using a pre-bagged, flowable micro-concrete. In total, CRL completed full repairs to 125 deck ends and over 4,500 individual mid-span locations, including a single large-scale deck replacement repair covering 200 m². The magnitude of delivery is reflected in the consumption of 10 million litres of water for hydro-demolition, 1.5 million kilograms of repair material and the installation of 21,000 sacrificial anodes. Almost 350 personnel contributed to CRL’s section alone, demonstrating the company’s capacity to resource, manage and deliver complex, large-scale structural repairs UK projects efficiently and safely.
