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Questions related from Nick Ryland Barton
There seems to be an increasing number of MSc or PhD studies by young students with little tunnelling or TBM experience. They compare numerous established prognosis methods, and regrettably make...
19 January 2022 6,125 3 View
Engineering geologists may know that the originators of the empirical (a posteriori) Q-system method of rock mass classification for single-shell tunnel and cavern support estimation, were Barton...
14 December 2020 5,233 3 View
There are so many tunnel excavations, and so many who use either 'observational' (maybe double-shell) NATM or single-shell B + S(fr) selection from Q, or RMR, or less frequently RMi. Many then ask...
22 April 2020 3,828 9 View
Very frustrating to not know how to do this!
14 September 2018 6,450 2 View
Baotang Shen, the developer of FRACOD, using classic theory linking stress anisotropy and Poisson's ratio to explain exceedence of critical extension strain in a fully 3D compressive stress field,...
16 April 2018 6,240 4 View
Shear stiffness Ks is an entirely different parameter to normal stiffness Kn, despite being given the same units such as MPa/mm or the equal GPa/m. Because Ks is doubly scale-dependent (peak shear...
05 April 2018 9,766 9 View
Quote from TUST article of 2010, just seen: During tunnel excavation in a jointed rock mass, significant joint closure takes place in the immediate vicinity of tunnel due to joint effective...
16 December 2017 5,706 2 View
The 'standard' set of 10 JRC profiles, chosen from about 400 measurements on 130 joint profiles, are 2D and for guidance only. Of course subjective in nature when used for estimation. Why so few...
14 December 2017 3,102 0 View
With water pressure from melting surface water sometimes exceeding the vertical ice load of 1 or 2 km, sub-horizontal hydraulic fractures are sometimes (often?) found some 10's of meters below...
27 November 2017 9,928 1 View