Q system

GPTKB entity

Statements (23)
Predicate Object
gptkbp:instanceOf rock mass classification system
gptkbp:appliesTo mining
tunneling
rock engineering
gptkbp:citation Barton, N., Lien, R., and Lunde, J. (1974). Engineering classification of rock masses for the design of tunnel support. Rock Mechanics, 6(4), 189-236.
gptkbp:component Ja (Joint alteration number)
Jn (Joint set number)
Jr (Joint roughness number)
Jw (Joint water reduction factor)
RQD (Rock Quality Designation)
SRF (Stress reduction factor)
gptkbp:developedBy NGI (Norwegian Geotechnical Institute)
https://www.w3.org/2000/01/rdf-schema#label Q system
gptkbp:introducedIn 1974
gptkbp:parameter Q value
gptkbp:Q_value_formula Q = (RQD/Jn) × (Jr/Ja) × (Jw/SRF)
gptkbp:relatedTo RMR system
rock mass rating
gptkbp:usedFor tunnel design
rock mass classification
underground excavation stability assessment
gptkbp:bfsParent gptkb:GAL4/UAS_system
gptkbp:bfsLayer 6