Permanent Reinstatement of Concrete Manhole Cover on A406 North Circular Road
Background
Urgent repairs were needed to a dilapidated concrete infill manhole cover in the western bore of Fore Street Tunnel.
This forms part of a heavily trafficked main ring-road around London. The first thought was to make a temporary localised repair with an acrylic/epoxy flexible filler and return some 10 days later to effect a permanent repair to the whole cover. Working immediately adjacent to fast-moving traffic, the contractor needed to reinstate the integrity of the surface within a very tight working window.
The Solution
Fastfill, an OPC based fast setting fibre reinforced structural repair mortar, was proposed and used with great success. Fastfill has the speed and ease of application of a temporary repair solution but the strength and resilience of a permanent concrete repair, removing the need for two separate operations. In this case, the Fastfill repair was laid and, within as little as two hours, subjected to the usual heavy traffic volumes. Impressed by the result, the client, Transport for London (TFL) will be recommending its use on similar projects in the future.