Macro–meso failure mechanism of soil–rock mixture at medium strain rates

Uniaxial compressive strength experiments at medium strain rate were conducted to characterise rate effects and the macro–meso failure mechanism of a soil and rock mixture (SRM) with different rock block percentages using a servo-hydraulic variable frequency dynamic machine. Macroscopic failure morphology descriptions and meso three-dimensional laser scanning techniques are used to investigate internal failure mechanism. The results indicated that SRM specimens experience splitting failure, shear failure and conical failure with increasing strain rate. The cumulative fracture width and surface toughness were dependent on the loading rate, which were the results of interaction between rock blocks and the soil matrix and induced by the intrinsic fracture mechanism.