STOCHASTIC DYNAMICS OF DAMAGE EVOLUTION IN BRITTLE ROCKS

Development of defects in brittle rocks is analysed in terms of contin uous damage mechanics with an emphasis on a shear damage evolution. Ne cessity to account for an effect of stochastic action leads to an intr oduction of kinetic relations for damage accumlation in a form of stoc hastic differential equations. Numerical algorithms for their solution for three types of noise are proposed. Results of simulation are comp ared with analytical solutions for a determiistic case (absence of sto chastic action). Effect of various types of noise on damage accumulati on and on time-to-fracture distributions is investigated. The study is limited to the case of temporal stochasticity; ways for unification o f approach and schemes with spatial randomness are discussed.