Slope mass rating (SMR)

For evaluating the stability of rock slopes, Romana (1985 ) proposed a classification system called slope mass rating (SMR) system. Slope mass rating (SMR) is obtained from Bieniawski’s rock mass rating (RMR) by subtracting adjustment factors of the joint-slope relationship and adding a factor depending on method of excavation, 18.1 https://www.w3.org/1998/Math/MathML" display="block"> SMR = RMR basic + F 1 ⋅ F 2 ⋅ F 3 + F 4 where RMR basic is evaluated according to Bieniawski (1979 , 1989 ) by adding the ratings of five parameters ( Singh and Goel, 1999 ). The F 1 , F 2 , and F 3 are adjustment factors related to joint orientation with respect to slope orientation and F 4 is the correction factor for method of excavation. These are defined below: