Investigation of position marlston in rock mass enginnering classification system,case study: Doosti Dam

With investigation 60 meters from 7 exploratory boreholes Q, RMR, RSR and RQD classification systems calculated and compared Studies show that some categories do not apply marl rocks.Whether or not the marlstone with a quality category limit. There is exponential, linear and logarithmic equations differences between the classification systems in marlstones with what is established other rocks. The result needs marlstone to other engineering rock mass classification systems. RQD classification alone cannot describe the quality Marlstone. As the applied stress due to the behavior of ductile rocks, marlstones are category also hard stones and resistant. RMR classification changes under the normal curve is symmetrical closer and marlstones are classified into two categories Q extremely weak and very weak, and therefore is more suitable than the other classification systems. Key words: Engineering classification of rock masses, marlstones, geological engineering,Doosti dam ,Abtalkh formation.Key words: Engineering classification of rock masses, marlstones, geological engineering,Doosti dam ,Abtalkh formation.