Study on mechanical parameters of fractured rock masses

Abstract

The equivalent strength parameters of fractured rock masses are prerequisite for stability analysis of geotechnical engineering projects constructed in fractured rock masses which are encountered frequently in western china. Based on generated mesh of fractured rock masses, combined with statistic damage constitutive model of intact rock and damage model of structural plane, progressive failure of fractured rock masses is studied using finite element method (FEM). Furthermore, Scale effect and anisotropy of compressive strength of fractured rock masses are studied. Study results show that the strength decreases and tend towards stability rapidly from intact rock to fractured rock masses, and the anisotropy of strength of fractured rock masses is not significant. At last, based on numerical simulation conducted on 10 m scale rock masses under different confining pressures, the equivalent strength parameters of fractured rock masses are gained and the results are compared with Hoek-Brown criteria. The method developed is helpful for determination of strength parameters of fractured rock masses.