عنوان مقاله [English]
نویسنده [English]چکیده [English]
Limit equilibrium method is one of the methods for stability analysis which is based on the stresses on the fracture plane. Stresses on the fracture plane are estimated based on the linear Mohr-Coulomb and non-linear Hoek-Brown criteria but, resulted data differ from the real stresses on fracture plane. Hence, determining the stresses on the fracture plane is considerable for the rock mechanics researchers. In the present paper, stresses on the fracture plane in brittle rocks are investigated using Coulomb theory and concept of Mohr circle. First, fracture plane is determined based on the Coulomb theory and then, using Mohr stress circle stresses on fracture plane are estimated. To validate the results, Mohr-Coulomb and Hoek-Brown criterions and Mohr stress circle which gives the real values for stresses on the fracture plane are used. Study shows that there are differences between obtained results from two criterions and Mohr stress circle, and results depend on the Mohr-Coulomb and Hoek-Brown envelopes. While according to the Coulomb-Mohr theory, stress on the fracture plane is determined using results of one experiment considering behavior of rock, and is estimated according to the real fracture plane.