השוואת שיטות

	מערכת Q	קריטריון כשל Hoek-Brown
תחום	הנדסת כרייה	הנדסת כרייה
משפחה	Process / pipeline	Process / pipeline
שנת המקור	1974	1980
הוגה השיטה	Nick Barton (Norwegian Geotechnical Institute)	Evert Hoek and E. T. Brown
סוג	Empirical index for tunnel support and stability prediction	Empirical criterion for rock mass strength prediction
מקור מכונן	Barton, N., Lien, R., & Lunde, J. (1974). Engineering classification of rock masses for the design of tunnel support. Rock Mechanics, 6(4), 189-236.	Hoek, E., & Brown, E. T. (2002). The Hoek-Brown failure criterion and GSI: 2018 update. Journal of Rock Mechanics and Geotechnical Engineering, 10(2), 445-463.
כינויים	Q Index, Norwegian Geotechnical Institute Classification, Barton System	Generalized Hoek-Brown Criterion, HB Criterion
קשורות	3	3
תקציר	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.	The Hoek-Brown Criterion, developed by Evert Hoek and E. T. Brown starting in 1980, is an empirical failure criterion that predicts the shear strength of rock masses as a function of confining pressure. It accounts for rock quality (via the Geological Strength Index, GSI) and thus bridges laboratory rock mechanics and field behavior. The criterion is widely used in mining for slope stability, pillar design, and stress analysis.