Dimensional Effects on Dynamic Properties and the Relationships between Ultrasonic Pulse Velocity and Physical Properties of Rock Under Various Environmental Conditions

The ultrasonic pulse velocity (UPV) test is an extensively used, nondestructive, and simple test to delineate the dynamic properties of rocks for geotechnical and rock engineering applications under various environmental conditions. Rock materials that host engineering applications must be studied in detail under laboratory or in situ conditions. However, generally, in situ practices are more expensive and time consuming than those undertaken in the laboratory. The present work aimed to investigate (i) how existing core samples with different sample diameter (D) and sample length (L)/D values affect the dynamic properties of rock materials and (ii) the relationships between UPV and physical properties under various environmental conditions. In total, 190 limestone core samples with five different diameters and various lengths were prepared. UPV, density (ρ), unit weight (γ), specific gravity (G_s), water absorption (w_c), and porosity (n) tests were conducted on the core samples according to suggested standards. Results reveal that (i) the dynamic properties of limestone under different environmental circumstances change with sample D and L/D, and (ii) relationships exist between the UPV and the physical properties of limestone. Consequently, it is possible to use the correlation equations presented in this study to assess dynamic features and predict UPV values based on the physical properties of limestone, particularly during the preliminary stage of engineering works. However, this should be done with caution and only for the selected rock type.