Dynamic Mechanical Properties of Coals Subject to the Low Temperature-Impact Load Coupling Effect

The effects of low temperature gradient on dynamic mechanical properties of coal were examined through Split-Hopkinson Pressure Bar (SHPB) Dynamic Impact Experiment, the law of dynamic mechanical parameters of coal specimen changing from room temperature to negative temperature (25 °C, −5 °C, −10 °C, −15 °C, −20 °C, −30 °C, −40 °C) was analyzed, and the coal-rock stress-strain curve characteristics subject to the low temperature-impact load coupling effect was discussed. The law of the effects of different strain rates on the rock strength properties and the compressive deformation and failure was analyzed by studying the coal specimen at −15 °C. Moreover, the mechanical properties of coal specimen in saturated and dry conditions were compared, and the effects of water and water-ice phase transition on the strength properties of the corresponding coal specimen were analyzed.