Ultrasonic shear wave response to mechanical parameters in single-jointed rock masses: an experimental investigation of rock fragmentation effects
摘要
The propagation of ultrasonic waves through jointed rock masses exhibits significant complexity. Currently, limited research exists on the correlation between shear wave acoustic parameters and the elastic modulus of fractured rock masses with varying degrees of fragmentation. This study investigates the propagation characteristics of ultrasonic shear waves in single-jointed rock masses, with particular emphasis on the effects of different fragmentation levels. Synthetic rock-like specimens with single joints and graded fragmentation were prepared using analogous materials. Through integrated axial compression tests and ultrasonic measurements, the propagation characteristics of shear waves – including wave velocity, peak amplitude, and energy attenuation – and their relationships with elastic modulus were systematically analysed. A normalized sensitivity analysis was conducted to quantitatively assess the impact of fragmentation degree on acoustic parameters and mechanical properties. The results demonstrate that fragmentation degree significantly influences shear wave propagation characteristics, with peak amplitude showing the highest sensitivity to structural changes in rock masses. A predictive model was developed to estimate the elastic modulus of single-jointed rock masses based on ultrasonic shear wave parameters, providing a non-destructive approach for evaluating rock mass quality in geotechnical engineering applications.
Research highlightsInvestigated the relationship between ultrasonic shear wave parameters and fragmentation degree in single-jointed rock masses. Identified peak amplitude as the most sensitive acoustic parameter for detecting structural changes in fractured rock. Developed a predictive model for estimating elastic modulus based on maximum shear wave amplitude.