![For a granitic rock mass, joint set number (Jn) = 9, joint water reduction factor (Jw) = 1](https://www.gkseries.com/blog/wp-content/uploads/2023/10/For-a-granitic-rock-mass-joint-set-number-Jn-9-joint-water-reduction-factor-Jw-1.jpg)
Q. For a granitic rock mass, joint set number (Jn) = 9, joint water reduction factor (Jw) = 1, joint alteration number (Ja) = 1, stress reduction factor (SRF) = 1, rock quality designation (%) = 84 and joint roughness number (Jr) = 3. The Q-value as per Barton’s Q-system of rock mass classification (year 1974) is
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