Geomechanical state of jointed rock pillar with the account of softening behaviour

The paper presents the methodological basis for predicting the geomechanical state of structurally disturbed rock pillars taking into account the limit stage of their deformation. The paper also includes virtual tests of rock mass samples and rock pillars, analysis of the results according to the uniaxial compression scheme taking into account the off-limit stage of their deformation, revealing the influence of rock mass discontinuities parameters on the strength of pillars with different aspect ratios, formation of pillar stress-strain diagrams and deformation diagrams in the axes of principal stresses and relative strains. The mechanism of virgin pillar deformation is considered explicitly using numerical modeling. The paper describes the procedure of parameter selection of the Hooke-Brown model with unstrengthening for a jointed rock mass based on the results of virtual experiments on the rock mass. The research was supported by a grant from the Russian Science Foundation (project No. 23-17-00144).