Обґрунтування вибору моделі вибухового руйнування скельного гірського масиву в програмному середовищі ANSYS AUTODYN

The paper presents the results of research on the selection of the model of rock massif destruction by explosion of a borehole charge in ANSYS environment with the use of the program complex of engineering analysis AUTODYN, as well as the calculation of the process of explosive crushing of granite. The joint use of Euler and Lagrange reference systems is an undoubted advantage of ANSYS AUTODYN. Such calculation allows modelling simultaneously the action of stress waves in the solid medium and the action of explosion gases, which form the crushing funnel by penetrating into the cracks. The results obtained showed the effectiveness of this software product and the reliability of the data obtained. In the scientific article the choice of equations of state of the medium model for each material is justified: for granite mass – Riedel-Hiermeier-Thom (RHT) model equation; for explosive – Johnson-Wilkinson-Lee (JWL) equation of state; the behavior of the borehole is described by the Drucker-Prager model; for air is characterized by the ideal gas equation of state (Boyle and Gay-Lussac laws). The results of modeling of the explosion action of the Anemix 70 borehole charge in the rock massif of the Pinyazevitsky granite deposit showed that the active destructive pressure of the explosion gases acts in the rock for 0,35 ms. Further, deformation and destruction of a massif occurs at the expense of the accumulated loads and inertia of flight of pieces of a rock. Thus, the useful effect of kinetic energy continues up to 1,0–1,5 ms. The epura of destruction of the granite rock massif, which is obtained from the results of modeling in ANSYS AUTODYN, also showed the destructive effect of the explosion in the bottom part of the borehole charge. It was found that the rock mass is destroyed to a depth of 0,7 m from the bottom end of the charge.