Construction of Retaining Wall

The existing highway retaining wall had partially collapsed. This supported a single track road with only a very narrow alternative access for residents of the village.

Work comprised of:

• Setting up a road closure while maintaining pedestrian access throughout the work
• Careful demolition of the masonry wall was carried out, whilst retaining the masonry to clad the new wall
• Excavation in the highway was undertaken to accommodate the new structure, supporting an existing water main and BT services
• Excavation to bedrock, 2.6 metres below road level, a toe was cut in, dowels inserted, and a reinforced foundation slab poured
• The retaining structure consisted of dense concrete block on flat, 900mm wide at the base reducing to 450mm at road level. Drainage holes were provided from a carrier at the rear of the wall, a drainage blanket was incorporated with waterproofing of the structure, drainage provided to the rear wall.
• The retained masonry cladding, 250mm thick, was tied to the mass block structure. Expansion joints were incorporated throughout. The masonry face had a slight incline to match the existing. A masonry parapet was constructed with “Cock and Hen” coping. All masonry was built using lime mortar.
• Finally, a kerb to retain traffic was installed along the wall, with concrete to the rear to seal from water, and the carriageway was re-surfaced.

The original contract required a 5 metre wall, however, during construction, a further 5 metres was found to be unsafe and this was also reconstructed. The location of the work was a very confined site with narrow and sloping access, necessitating constant attention to, and communication with, residents and land-owner.