TBM Ada - Crossrail Drive X
London, UK (Royal Oak to Farringdon) · 2012-2014 (Based on the paper and general Crossrail tunnelling dates) · £14.8bn (Crossrail project total)
The judgement call
Account-gated at launchTBM reception arrangements for Drive X were modified due to construction complexity at Farringdon station, requiring TBMs to be driven on tight curves and stripped down/concreted in place, with back-up trains removed from Fisher Street crossover. This was not considered optimal due to time consumption and health/safety hazards of underground cutting and burning.
Key engineering challenges
Dealing with significant quantities of different excavated material. - Minimising environmental impact from transportation and disposal. - Minimising settlement effects. - Dealing with multiple TBM launches and receptions.
Project facts
- Client / owner
- Crossrail Ltd.
- Lead contractor
- —
- Lead designers
- CH2M, Atkins Ltd
- Project type
- new build
- Scale
- TBM type: Earth pressure balance; Drive length: 6.8 km; Total tunnelling time: 522 days; Tunnelling time excluding delays: 313 days; Average progress including delays: 8.9 rings/day; Average progress excluding delays: 14.9 rings/day; Maximum progress: 48.0 m/day (38 rings/day, 185 rings/week)
- Disciplines
- civil; structural; mechanical; electrical; systems; tunnelling; geotechnical
- Standards & frameworks
- ICE Proceedings, CDM Regulations (implied for UK projects of this scale)
Sources: King, M., Thomas, I., & Stenning, A. (2017). Crossrail project: machine-driven tunnels on the Elizabeth line, London. Civil Engineering, 170(5), 31-38. (https://dx.doi.org/10.1680/jcien.16.00028) - Crossrail Learning Legacy (https://learninglegacy.crossrail.co.uk/)