Geotechnical earthworks – M74 completion project

In order to improve traffic through-flow in the southern suburbs of Glasgow, a new 8 km section of the M74 motorway was designed and constructed.

Summary of the Works

Client – Interlink (JV of Sir Robert McAlpine, Balfour Beatty and Morrison Construction)
Contract name – M74 Completion Project, Glasgow
Approx. Value – £480,000
Start Date – July 2008
Completion Date – May 2012

The project included the construction of 14 bridges, one two-way junction where the M74 meets the M8 and three four-way junctions. The construction was made particularly difficult due to the congested urban environment, the proximity to the railway and a considerable amount of contaminated land.
ITM Monitoring, now SOCOTEC Monitoring UK Ltd, was contracted by Interlink to install various Vibrating Wire Piezometers and Inclinometers beneath the motorway corridor and numerous bridge abutments. These were cabled back to junction boxes via trenches and manually read by Interlink operatives. The installation was made difficult due to the quantity of chromium contaminated land. This was largely controlled through the use of a ‘sonic’ rotary drill rig operated by Boart Longyear which ensured contaminated spoil was contained at all times and dramatically reduced exposure.