Costain/VINCI Construction Grands Projets JV (CVJV) has completed the construction phase of Scotland’s biggest waste water tunnel, the 5km long, 4.7m diameter Shieldhall Tunnel following the breakthrough of its 5.51m diameter Herrenknecht slurry TBM on the evening of the 12th October.
The state-of-the-art TBM was launched in July 2016 and has spent 15 months boring and erecting over 3200 segmental rings on the $140M tunnel beneath the south of the city between Craigton and Queen’s Park via Bellahouston and Pollok parks. Construction of the single pass segmental lining has been through an array of ground conditions, at a depth of as little as 4m from ground level to crown. There have been clays and made ground, sandstone and mudstone, glacial till with boulders and the remains of mine workings at various depths to deal with.
The tunnel is described as ‘one of the most important pieces of waste water management infrastructure installed in Glasgow since Victorian times.’
With this key phase of the project now complete, further construction and ancillary work will be carried out including work to connect the tunnel to the existing waste water network before the tunnel becomes operational next summer.
(Full article TJ September 2017, p32)