Statistical Damage Simulation Of Full Deformation Process For The Rock Under High Stress

With the decrease of the shallow resources, developing into the deep mining has become the trend of the mineral resources exploitation at home and abroad. Deep rock in "three tall one disturbance" complex environment which makes the deep rock mass have obvious different mechanical properties compared to the shallow rock,causing the rock burst, water inrush, large area roof weighting and instability of mined-out area, such as severe accident in degree aggravate, frequency to increase at the same time, by mechanism is more complicated. In-depth research under the condition of high stress rock mass mechanics to avoid major accidents occurred in the process of deep resources exploitation has important theoretical guiding significance and practical significance. And the whole process of rock deformation simulation can help to understand the mechanical properties of the rock. So in order to better interpret the mechanical properties of deep rock, suitable high stress conditions of statistical damage constitutive model of rock is presented in this paper.To build the simulation method which can reflect the whole process under the condition of high stress rock deformation, first of all, the present related research results at home and abroad were summarized and concluded, criteria adapting to the conditions of rock strength was learned, the deformation mechanism and the deformation process of rock material was discussed, the thorough research to the mechanical properties of the rock has been carried to lay the foundation for establishing the constitutive model of the rock.The nonlinear Mohr-Coulomb strength criterion is applicable under the condition of high stress rock and the corresponding micro-unit strength measurement method was put forward. Meanwhile, statistical damage theory was introduced and the statistical damage constitutive model was built considering that damage threshold had the influence on measurement method of rock damage. Secondly, the determination methods of the model parameters were given according to the features of rock triaxial test curve and based on the relationship respectively between confining pressure with peak stress and peak strain, the statistical damage constitutive model that could reflect deep earth rocks deformation under different confining pressure was constructed.Based on the modification of Hoek-Brown criterion, make it can describe the damage of rock under high stress conditions, and the introduction of statisticaldamage theory, considering the influence of the residual strength of rock damage,statistical damage constitutive model is established.Finally, the trial curves were compared with the prediction curves of the proposed model in this paper. The results show that the proposed constitutive model could reflect the deformation process of deep earth rocks, simultaneously, it may also reflect the properties that rock strength changed with confining pressure. The feasibility and rationality of the proposed model and method were indicated.