Latest from Tunnels and Tunnelling


Tunnel could replace Brooklyn-Queens Expressway
27 February, 2020 New York – The New York City Council and Arup released a report February 24 about the possibilities for repairing and replacing the Brooklyn-Queens Expressway, including a tunnel.
  • TBMs leaving site on the Sydney Metro project
    Australia – The four 7m-diameter Herrenknecht double shields that excavated the tunnels for the City & Southwest phase of the Sydney Metro are being lifted out of construction sites and are leaving the city. Between them they have excavated 30km of twin metro tunnel and only the slurry TBM for the harbour crossing remains.
  • First Forrestfield TBM makes final breakthrough
    Australia – The first TBM mining the Forrestfield-Airport Link in Perth has broken through. ‘Grace’ broke through into the Bayswater dive structure in February and will be followed by ‘Sandy’ in May, which is tunnelling the typical three-months behind the lead machine. The contractor is the Salini Impregilo-NRW JV.
  • HSE issues welding warning
    Great Britain – The Health and Safety Executive (HSE) has issued a reminder that companies must protect their workers from the risks from welding fume. The HSE is undergoing a programme of inspections following a February 2019 safety alert. New evidence showed that exposure to mild steel welding fume can cause cancer.
  • Thames Tideway excavation halfway complete
    Great Britain – London’s new ‘super sewer’ half excavated. The TBMs boring the Thames Tideway project are 12.5km through the 25km-long, 7m-diameter project. As well as the main tunnel, a 1km-long, 3m-diameter connection tunnel is also currently under construction in Wandsworth at the western end of the project.


ASA publishes position statements for underground shotcrete
20 February, 2020 Axel Nitschke, tunnel practice leader (NATM), for WSP USA , is chair of the ASA Underground Committee. He gives background on two new papers from the association
  • Underground Maze
    Paola De Pascali visited the Bank Station Capacity Upgrade (BSCU) site, which is placed in the City of London within historical buildings and Roman archaeological remains
  • Encountering Pingoes
    A slurry TBM encountered an unexpected drift filled hollow (DFH) on the Lee Tunnel drive. Three contributors told their part of the story: project geotechnical engineer Tim Newman gave a description of the project and some of the GI undertaken ahead of the drive, tunnel construction manager John Corcoran spoke about tunnel operations and consultant geologist Jackie Skipper about emergency response site team, forensic ground investigation to gauge extent of DFH, what is a DFH and tell-tale signs. Martyn Noak from Jacobs reports
  • Hunting the record
    Romed Insam from Brenner Base Tunnel SE and Michael Rehbock-Sander, head of engineering at the Brenner Base Tunnel North JV, working for Amberg Engineering, report on the challenges and the current state of the future longest tunnel in the world
  • Alan Thomas Winter (1952-2019)
    It is almost a year since Alan died unexpectedly in January 2019. Those who worked with Alan respected his immense knowledge and vast practical experience that he brought to bear for the benefit of numerous projects and clients. In addition, Alan was also well known and admired for his sense of humour and quick ability to add wit to alleviate the stress of crisis.