Study on fractal and energy dissipation characteristics of rock impact fragmentation in Junggar basin

Abstract

In order to study the rock energy absorption and crushing fractal characteristics under impact load, the dynamic impact tests of rock in J1b formation in Junggar Basin were carried out by split Hopkinson bar. The strain rate effect on the crushing energy consumption and failure mode were analyzed. Combined with fractal dimension calculation and energy density analysis, the energy density and fractal characteristics of rocks during the impact process are studied. The results showed that the strain rate and energy density of the specimens are in line with the power relationship, the energy density increases with the strain rate, and the fractal dimension increases significantly with the increase of the strain rate, the energy density and fractal dimension of the specimen under dynamic load conform to a power relationship. The more energy absorbed by the rock, the more obvious the fractal characteristics are. The energy density combined with the fractal dimension calculation of rock fragmentation can quantitatively study the energy absorption law of rock per unit time.