Highways Agency

Project

Queenhill Viaduct was built in 1960 and carries the M50 Motorway over the River Severn and its flood plain.  Between November 2006 and April 2007 an investigation was carried out to look at the condition of the structure.  The investigation was concentrated on the condition of the joints and bearings and was carried out from the land beneath the viaduct.

In particular we were looking at a concealed steel corbel detail that can only be exposed by removing small cores of concrete to reveal the steelwork.  The core removal was carried out by a specialist using a high pressure water jet.  The process is carefully controlled and precise areas can be removed without damaging the reinforcing steel.  The removal of small cores has no effect on the stregth of the viaduct and traffic was not affected or restricted by the investigation works.

Information gathered from the investigation will allow us to plan future maintenance more efficiently.  The investigation was delayed by winter flooding beneath the viaduct but was finally completed in April 2007.  The results showed that the corbels that were exposed are in reasonable condition.

Traffic Management

In order to access the site safely, cones and signs were placed on the westbound sides of the viaduct. 

Access and egress to the site was restricted to vehicles fitted with warning beacons which had to use the access points at the back of the hardshoulders.

Temporary Lane 1 closures were required in the westbound direction to allow bulky materials to be moved on or off the site (for example the scaffold tubes and boards).  These closures were of short duration and were scheduled for times of the lowest traffic flows, such as mid-mornings on a weekday.  No delays were recorded as a result of the traffic management.