Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/775086
Front line At any one time, there is usually a team of about eight working on the TBM, driving or piloting it and operating equipment used to excavate material. Another 20 support staff work behind it installing the tunnel sections (six of the concrete segments are installed to form a 1.5m-long ring) and the pipework or ducting for water and air and to transport the slurry back to a slurry treatment plant above-ground. The support staff also use the train to bring parts, supplies and spares to the TBM. The machine has a cutting wheel with 25 cutters at the front, which rotate as it moves forward at the speed of about two millimetres per minute. The TBM has to lay six of the concrete wedges to create one circular ring and the teams aim to lay about 24 rings per day. Perhaps surprisingly, it's work that the engineers relish. Tom, who's 25 and from Birmingham, says: "It's really fantastic to be working on such an important project, the first of this type and size in Scotland, which will benefit Glasgow for generations to come. "I enjoy working in tunnels and, although it's a challenge carrying out very technical work in these conditions, it's one I relish and enjoy every day. "You quickly get used to the confined space and we have everything we need down here for working long shiŽs – including a kitchen and toilet! "Getting to my current 'place of work' is certainly quite different to what most people do every morning above ground. But I would never want a conventional office job. Building tunnels is cool and I really wouldn't swap it for anything." The machine is on schedule and expected to complete its journey and emerge at Queen's Park in the summer of 2017, aŽer which the new tunnel will be connected to the existing network and the project completed by about the end of 2017. Inevitably, as the tunnelling progresses and the TBM gets further along its 3.1 mile-long route, the men's journey will also get longer. Their 'commute' at the moment takes little more than 10 to 12 minutes from entry shaŽ to the back of the TBM. In the final stages of the tunnelling work, when the TBM is further away from the shaŽ where the tunnelling began, that journey will take almost 30 minutes. Today, aŽer another hard day's graŽ carrying out work deep underground in conditions that few of us would enjoy, the workers make the same journey in reverse, taking the 'train' from the TBM back to the entry/exit shaŽ, climbing the stairs and checking out at ground level. Just like all commuters, the engineers are delighted to get to the end of their journey from work each day and, again like the rest of us, they go home, eat and relax ….and get ready to do it all over again tomorrow. An accompanying video of Tom Rushe and the Shieldhall Tunnel team is available at http://tinyurl.com/jex87gn The tunnel is 4.65m in diameter The TBM has a long, narrow gantry running down its side The train in the tunnel currently takes 10-12 minutes to reach the TBM The entry sha of the tunnel is the hub through which everything goes in and out 12 | FEBRUARY 2017 | WWT | www.wwtonline.co.uk