Experimental Evaluation of Dynamic Test Methodologies for Assessing the Elastic Constants of Granitic Rocks

Two dynamic test methodologies, the resonance method and the ultrasonic method, are used for assessing the elastic behaviour of granitic rocks. The experimental results obtained using two types of specimens: (i) rectangular beams (parallelepiped specimens); and (ii) cylindrical specimens (rod specimens); show that the resonance method used in this work is more adequate when both Young's modulus and Poisson's ratio are to be determined in these types of rocks. Moreover, it is demonstrated that test results obtained by resonance techniques are less dependent on specimen's geometry, size, and even surface roughness.