EXPERIMENTAL STUDY OF ENERGY CONSUMPTION IN FRACTURE AND FRAGMENT SIZE DISTRIBUTION OF ROCK UNDER INTERMEDIATE STRAIN RATE LOADING

摘要

In order to determine the relationships between fragments distribution characteristics and energy consumption of rock under intermediate strain rate loading,the granite specimens were tested with large-diameter Split Hopkinson Pressure Bar(SHPB) equipment under the strain rates ranging from 50s-1 to 100s-1. The resulting fragment distribution was obtained by sieving of the fragments and the energy consumption was evaluated from the recorded stress pulses under different strain rate loading conditions. The experimental results showed that the higher the energy consumption density was, the greater the degree of fragmentation was, and the higher the incident energy and the strain rate of loading was needed. At the same time, the dynamic strength of specimen increased with the increasing of energy consumption density of specimen. Fitting curves indicated that the energy consumption density of rock formed a good power relation with strain rate and dynamic strength, and a linear relation with fragment size and incident energy.