Damage modes and energy characteristics of rock-like materials under dynamic load

An in-depth research is carried out on damage modes and energy characteristics of rock-like materials, with the whole impact process of spit Hopkinson pressure bar (SHPB) being simulated by ANSYS/LS-DYNA. A comparison between the experimental stress-strain curve and the curve derived from numeral simulation is made, the model's efficacy is proved; and the transmitting process of effective stress within the specimen is duly analyzed, three modes of damage are identified: tearing strain damage, axial splitting tensile damage and crushing damage. By analysing the history curve of specimen internal energy obtained via numerical simulation, it is found that the internal energy has an evident strain rate effect: at lower strain rate, the time history of the internal energy can be divided into two stages, and at high strain rate it can be categorize into four stages.