Latest from Tunnels and Tunnelling


TBM breaks through on Brenner exploratory tunnel
07 July, 2020 Final breakthrough has occurred on the 16.5km-long exploratory tunnel of the Tulfes-Pfons section of the Brenner Base Tunnel (BBT), Austria. Following assembly inside a cavern 3.5km deep inside a mountain, the 7.9m-diameter hard rock, Herrenknecht open-gripper TBM (‘Gunther’) started mining on 26 September 2015 from Ahrental eastwards to Steinach, drilling through hard rock to break through on July 6 2020.
  • Three tunnels favoured for Prague ring road
    Prague could see three tunnels constructed on the north-eastern segment of its 83km-long outer ring road. The city council wants to see the section between Brezineves and Satalice tunnelled as far as possible.
  • Veteran TBM holes through on Tideway connection tunnel
    TBM Charlotte has completed her drive on an important connection tunnel that forms part of Thames Tideway, London’s 25km-long ‘super sewer’. Holing through on 2 July 2020 at Carnwarth Road, Fulham, southeast London, the 3m-diameter machine has been mining at average depths of around 30m on the Frogmore Connection Tunnel which has been excavated in two parts.
  • TBM sets new southern hemisphere record
    Auckland, New Zealand has witnessed a new pipejacking record for the longest single drive in the southern hemisphere by a TBM with a diameter greater than 3m.


A good dose of fibre
11 June, 2020 Steel fibre-reinforced concrete and its historic use in metro tunnels was the subject of discussion at a seminar hosted by steel-fibre maker Bekaert. Paola De Pascali reports
  • Impacts of extreme weather on tunneling
    One of the most noticeable results of global warming is an increase in the strength and occurrence of extreme weather events around the world. Many studies now show that more frequent heatwaves, heavy rain, snowfalls, and hurricanes are expected over the next few decades. This new reality requires more careful site and logistical planning for heavy civil projects – especially tunnelling sites – where extreme weather can have a significant impact in many different ways.
  • Crossover TBMS Tackle Mumbai Challenges
    JP Bayart, Jim Clark and John McNally of The Robbins Company report on the progress of two TBMs boring through challenging mixed ground conditions on Mumbai’s metro
  • A new type of Indian Jumbo
    An advanced automated tunnelling jumbo is excavating a 15.1km tunnel on a flagship railway project in northern India. Beatrice Rispal of Sandvik reports
  • Finally back on track
    HS2 has at last been given the green light, following the notice to proceed which is enabling four joint ventures to finalise their designs. Julian Champkin reports