Werrington Dive Under

UK, Werrington

Project synopsis

Detailed design of heavy civils structures and design of complex temporary works. Collaborative working with the contractor and other designers.

Contractor

Morgan Sindall

End client

Network Rail

Awards

Ground Engineering Magazine Awards UK Project with a Value over £3M (sponsored by Geobear Global)

Tony Gee's involvement in Network Rail’s £1.2bn East Coast Upgrade in January 2021 saw a nine-day operation to push an 11,000 tonnes, 155m curved box structure into place under the East Coast Main Line (ECML), known as the Werrington Dive Under.

Werrington Junction is located 6km north of Peterborough on the East Coast Main Line [ECML]. The original track layout required slow moving freight trains to cross the ECML. Grade separation of the rail lines is intended to alleviate pressure on the ECML and decrease congestion. This was achieved with a Dive-under for the Spalding tracks.

The track level ramps down to the south side, passes below the ECML and rises up to the north side. The main component of the ECML dive-under length is a 155m long curved concrete portal weighing circa 11,000 tonnes, with an in-situ concrete base slab.

The jacked portal was fabricated on a temporary slab to the north east side. The slab was supported on piles and incorporated pockets to enable pushing of the reinforced concrete portal. The lower parts of the portal were precast concrete incorporating bearing plates for vertical support and the lateral guide jacks.

The structure is curved in plan, so the design has allowed for sideways guidance as the portal moves forward.

The portal was pushed into position during a nine-day blockade. This is the first time that a curved Portal has been jacked in this configuration in the UK and ensured that long closures of the railway line were avoided.