Features Archive

Archive of features from the global tunnels industry

Features By Date

March 2021


Collaboration, communication and competence updated
25 March 2021 The following article by Bob Ibell, founder and director of London Bridge Associates, is based on a past Harding Lecture and has been updated by the author in celebration of the BTS 50th Anniversary

National grids
25 March 2021 Utility grid projects bring a variety of tunnelling challenges. Report by Patrick Reynolds

Review of ITA working group 12 PSCL linings
24 March 2021 Martin Knights, Independent Consulting Engineer, former ITA President and Chair of London Bridge Associates reviews the new ITA Working Group 12: Permanent Sprayed Concrete Linings guidelines

Grouting for ground improvement
24 March 2021 Grouting in underground projects refers to the injection of pumpable materials into soil or rock formations to change their physical characteristics. It is one of the most used ground improvement techniques for underground projects and tunnelling applications.

Brexit and its effect on standards
24 March 2021 Donald Lamont, a member of T&T’s Editorial Advisory Board and a member of ‘CEN/TC151 Construction machinery – safety’ looks at the impact of Brexit on machinery standards in the UK

Over the line
24 March 2021 Describing an early upgrade at Bank Station around 30 years ago during the DLR extension, Ken Spiby, then a Nuttall shift engineer, now LBA director, recalls some of his tunnelling experiences, extracted here from the BTS 50th Anniversary book

Tales of tunnelling
23 March 2021 The British Tunnelling Society was inaugurated exactly 50 years ago. Julian Champkin talked to its members about the society and its immense contribution to tunnelling

Past present and future
23 March 2021 This article, from September 1999 by Eric Snowdon and Myles O’Reilly examines the progress of UK tunnelling from the mid-19th century onwards, recounting innovations and achievements, examining present activity and assessing the prospects for UK tunnellers

February 2021


Drill and blast tunneling
25 February 2021 A form of blasting dating from the pre-explosive’s era involved excavating tunnels by lighting fires at the face and throwing cold water on the hot surface to crack the rock. Later on, blasting with black powder was invented and since then, there have been steady developments in explosives, detonating and delaying techniques, and in our understanding of the mechanics of rock breakage by explosives.

Laser scanning covers the points
25 February 2021 Laser scanning and 3D virtual modelling were critical tools in the refurbishment of a deep shaft on London’s Thames Water Ring Main, resulting in a better foundation for future repair and maintenance. Julian Champkin reports

Lord of the rings
25 February 2021 A new ring-build system is said to offer health and safety gains, but also cuts ring completion times by around a third - bringing significant cost savings. George Demetri reports

A service limit state design approach for SFRC tunnel linings
25 February 2021 Sotiris Psomas, Director of Tunnel Structures at Cowie UK, looks at how to estimate mean crack-width for ‘strain-softening’ SFRCs which are usually adopted in tunnel- and shaft-lining applications

Tight Manoeuvres
25 February 2021 Academia and site-based investigations are being combined in Norway to advance our understanding and performance of high-pressure grouting. Patrick Reynolds reports

January 2021


Hyperloop: Establishing The Basics
29 January 2021 In the recent ‘BTS Hyperloop Challenge (Tunnels for Hyperloop)’ report undertaken on behalf of the British Tunnelling Society, Bill Grose outlined the basic requirements for Hyperloop infrastructure. The following is an extract from the report.

Pushing for victory
29 January 2021 A National Grid project to push a 5km pipeline under an estuary of global importance to wildlife has resulted in the world’s longest pipeline river crossing in a tunnel, safeguarding the UK’s gas supply for a century and earning a place in Guinness World Records. Julian Champkin reports

Hyperbaric interventions
29 January 2021 Tunnel projects often use compressed air techniques to stabilise the tunnel face. Work in compressed air in tunnels – increasingly referred to as hyperbaric operations – began in the 1830s. Although Lord Cochrane obtained a patent for the concept of using compressed air to stabilise soft or loose-flowing ground at the face of an excavation, it was a Frenchman, Jacques Triger who is credited with first using the technique for shaft sinking in northern France. Around 1874, James Greathead designed a compressed-air shield to construct the Woolwich Tunnel in London.

Fire Performance of PC Segmental Linings
29 January 2021 Explosive spalling in tunnel linings during fires is often attributed to vapour pressure build-up within the segments. In this article, Stephen Doran suggests that there is another factor at play which is more responsible for the phenomenon

West Link’s Korsvagen Challenges
29 January 2021 Dr Klaus Rieker of Wayss & Freytag Ingenierbau discusses the various construction techniques and procurement methods used for tunnelling the Korsvägen Section of Gothenburg’s new West Link rail line

Grouting for ground improvement
28 January 2021 Grouting in underground projects involves the injection of pumpable materials into soil or rock formations to change their physical characteristics. It is one of the most commonly used ground improvement techniques for underground projects and tunnelling applications.

December 2020


The third way
16 December 2020 Genoa has a magnificent sea port but desperately poor communications inland. A third route is being developed under the mountains that surround the city. Julian Champkin reports