Correlation between P-wave velocity and some mechanical properties for sedimentary rocks

Seismic techniques, which are known as nondestructive geophysical methods, are commonly used by engineers working in various fields such as mining, civil, and geotechnical engineering. They are frequently employed to investigate certain properties of rocks. Ultrasonic measurements can be applied in various application areas such as rockbolt reinforcement1, blasting efficiencies in the rock mass2, the determination of degree of rock weathering3, determination of deformation and stress on rock masses4,5, and rock mass characterization6,7. A number of studies8–13 investigating ultrasonic propagation in fractured rock have been carried out. Some researchers14–16 used the P-wave velocity for the estimation of weathering depth of building stones. Many researchers have found that Pwave velocity is closely related to physical and mechanical properties of rocks17–25. The main factors that influence P-wave velocity in rocks are lithology, texture, density, porosity, anisotropy, grain size and shape, water contact, stress, temperature, weathering, alteration zones, pores and microcracks, bedding planes, and joint properties (roughness, filling materials, water, dip and strike, etc.). The relationships between P-wave velocity and rock density have been investigated by various researchers26–28 who have reported an increase in the density as the velocity increased. The influence of microcracks on P-wave velocity distribution has been studied by Babuska et al.29 and Jech et al.30. The effect of crystallographic preferred orientation of rock-forming minerals on P-wave velocities was examined by various researchers. The effects of fracture roughness on P-wave velocity for granite, marble, and travertine was studied by Kahraman31, who stated that Pwave velocity decreased as the fracture roughness coefficient values increased. Kahraman32 derived empirical equations in order to predict P-wave velocity of wet rock from the P-wave velocity of dry rock. Singh and Kripamoy33 revealed that P-wave velocity and uniaxial compressive strength (UCS) decreased as the quartz content increased, and decreased as the moisture content increased. They also reported a decrease in P-wave velocity as the silica content increased. Some of the empirical relationships between P-wave velocity and the UCS for different rock types found in the literature are summarized in Table I. Correlation between P-wave velocity and some mechanical properties for sedimentary rocks