Non-linear Shear Strength Model for Coal Rocks

Abstract

List of symbols c (MPa) Cohesion φ (°) Angle of friction σ1 (MPa) The maximum principal stress σ3 (MPa) The minimum principal stress or confining stress σ3max (MPa) Maximum confining stress σci (MPa) Uniaxial compressive strength (UCS) σci_fitted (MPa) Fitted UCS a Fitting parameter b Fitting parameter m Fitting parameter n Fitting parameter k Intermediate auxiliary parameter AAREP Absolute average relative error percentage N Number of tests RE Relative error R2 Correlation coefficient