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Q-System/Evidence
Method evidence record

Q-System

The Q-System (NGI Index), introduced by Nick Barton and colleagues at the Norwegian Geotechnical Institute in 1974, is an alternative rock mass classification to RMR. It combines six parameters into a dimensionless index Q ranging from 0.001 to 1000, where higher Q values indicate better rock quality. The Q-System is particularly valued for tunnel and underground excavation design due to its explicit consideration of joint roughness and groundwater effects.

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Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.

Q-System (NGI Index) for Rock Mass Classification
Taxonomic method record · process-pipeline / mining-engineering
  • Barton, N., Lien, R., & Lunde, J. (1974). Engineering classification of rock masses for the design of tunnel support. Rock Mechanics, 6(4), 189-236. · DOI 10.1007/BF01239496
  • Barton, N. (2002). Some new Q-value correlations to assist in site characterisation and tunnel design. International Journal of Rock Mechanics and Mining Sciences, 39(2), 185-216. · DOI 10.1016/S1365-1609(02)00011-4
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Same method familyHoek-Brown Criterionmachine-suggested · Relational suggestion, not evidence.Taxonomic bucketRock Mass Ratingmachine-suggested · Relational suggestion, not evidence.Same method familyStope Layoutmachine-suggested · Relational suggestion, not evidence.

Evidence status

Sources recorded, not reviewed

Bibliographic sources are present. Claim-level evidence review has not been performed.

Sources

2 recorded citations, copied from the method source record.

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