Site: Shakespeare Beach, Dover, Kent
Client: Network Rail
Contractor: Costain (South East Multifunctional Framework)
Scheme Engineer: Tony Gee and Partners
Products supplied: Bespoke Precast Stairs and Modular Substructure
Following a severe storm in December 2015, resulting in the partial collapse of 250 metres of sea wall and associated damage to the main Dover to Folkestone rail line, a 9 month programme of major work has been undertaken at Shakespeare Beach. Costain, the South East Multifunctional Framework partner to Network Rail, has constructed a 235 metres viaduct above the damaged wall, supported on 130 concrete columns. Additionally, in excess of 100,000 tonnes of rock armour stone imported from Norway has been placed to act as a breakwater in front of the existing failed wall.
The storm also washed away up to 2 metres of the beach and, as part of the overall scheme; there was a requirement to rebuild a public right of way from a footbridge at Wellards Way down to Shakespeare Beach, in the form of a new set of steps down through the rock armour.
Due to the significant issues involved with constructing something suitable in-situ, Costain contacted FP McCann to investigate an innovative approach in collaboration both with themselves and principal engineer Tony Gee and Partners using an off-site precast concrete system.
FP McCann was asked to develop a modular precast substructure to act as permanent formwork and support for the concrete stair flights already detailed by TGP. This modular structure took into account the logistical challenges in the transportation of the units, the lifting arrangements, and enabled the structure to be erected and secured in the short intertidal periods available for construction.
The precast concrete stair flight which FP McCann also supplied is buttressed on either side by the armour stone. The steps have been given an anti-slip surface by shot blasting, all undertaken offsite at FP McCann’s factory in Littleport, Cambridgeshire.
To allow for long term public access, the installed structure has made provision for the future erosion of the beach by extending well below the current beach level.
Commenting on the project Patrick Sexton, General Manager for FP McCann’s Specialist Precast Division, remarked “We worked closely with the Costain project team and our engineers Pick Everard, to provide a workable and practical solution, both from a manufactured and installed system perspective. This resulted in a successful conclusion to a logistically demanding project”.
Ian Arden Senior Agent for Costain on the scheme said, “As part of the Dover Sea Wall project, we were instructed to build a set of stairs to the beach. These steps had to be constructed in the intertidal zone, giving a working window of as little as 3 hours. FP McCann worked closely with Costain to develop a modular staircase utilising both standard and bespoke products. FP McCann’s engineered precast concrete structure accounted for both temporary and permanent load cases and met our detailed installation requirements. Their fabrication team were able to turn the production around very quickly, aligning to the site requirements and delivering the modules in a ‘just-in-time’ manner. FP McCann worked as a true partner throughout and their contribution was key in the delivery of this element of the project”.
For more details about FP McCann’s Specialist Precast Solutions, contact a member of our Littleport team on 01353 861416 or email: email@example.com