Statistical Analyses and Geotechnical Evaluation of Nubia Sandstone, Golden Triangle Area, Egypt

Great efforts had been made to use indirect non-destructive tests in the geotechnical evaluation of rocks, especially sandstones, employing different empirical equations. However, most these equations have derived from hard and compacted sandstones data; therefore, focus this research is on weak weakly aiming firstly obtain for estimating their characteristics, secondly demonstrate visualize correlations between studied variables, finally cluster samples based characteristics. To attain aims, twenty oriented block were collected Nubia sandstone, central Eastern Desert, Golden Triangle area, Egypt. These prepared tested according standard test methods, including uniaxial compressive strength (UCS), Brazilian tensile (BTS), Schmidt rebound number (SRN), porosity (n), bulk density (ρ), ultrasonic P-wave velocity (UPV). The loss ignition (LOI) was also employed as a physicochemical classifying indicating pores filling materials. results revealed that are characterized mainly by high n, low ρ, UPV values give an indication cemented sandstone with shallow burial diagenetic conditions. Based UCS elastic modulus values, classified very highly yielding rocks. regression analysis show satisfactory physical mechanical suitability obtained deduce properties. Principal component LOI, BTS, SRN, USC positive correlation each other correlated ρ UPV, which positively negatively n. agglomerative hierarchical clustering can group into three main clusters depending USC, n values.