Impact strength index, slake durability index and uniaxial compressive strength (UCS) are important properties of a rock mass which are used widely in geological and geotechnical engineering. In this study, the mechanical properties of one igneous, three sedimentary and three metamorphic rock types were determined in the laboratory and correlated with P-wave velocity. Empirical equations have been developed to predict the impact strength index, slake durability index and UCS from P-wave velocity, which may avoid the necessity for time-consuming and tedious laboratory testing. To check the sensitivity of the empirical relations, a t test was performed which confirmed the validity of the proposed correlations.

L’indice de durete, l’indlce d’alterabilite et la resistance a la compression simple sont des proprietes importantes d’une roche, largement utilisees en geologie de l’ingenieur et en geotechnique. Dans cette etude, les proprietes mecaniques d’une roche magmatique, de trois roches sedimentaires et d’une roche metamorphique ont ete determinees au laboratoire et correlees avec les vitesses des ondes P. Des equations empiriques ont ete etablies pour obtenir l’indice de durete, l’indice d’alterabilite et la resistance a la compression simple a partir de la vitesse des ondes P, ce qui permet d’eviter de realiser des essais de laboratoire consommateurs de temps. Afin de verifier la sensibilite des relations empiriques etablies, Ie test t de Student a ete mis en ceuvre et a permis de confirmer la validite des correlations proposees.