Estimating uniaxial compressive strength, density and porosity of rocks from the p-wave velocity measurements in-situ and in the laboratory

Knowledge of the physical properties rock masses is fundamental for economics and safety mining projects. The determination these in samples laboratory requires time, expensive equipment qualified personnel, which considerably increases information's cost. Indirect methods were developed to obtain related masses, have been shown be a viable alternative traditional procedures. compressional mechanical wave velocity (Vp) subsequent correlation with lithological are indirectly obtained. This study’s objective was correlations between Vp resistance uniaxial compression, UCS (Unconfined Compressive Strength), as well density porosity siltstone sandstone lithologies present coalfield Candiota, located southern region Rio Grande do Sul, Brazil. records obtained samples, using ultrasonic sensors, in-situ by geophysical logging (directly boreholes). results indicate possibility determine parameters investigated lithologies. In specific case Unconfined Strength, coefficients R2 above 0.70 obtained, indicating sufficiently high reliability this information (e.g. roof support projects). also high.