Determination of compressive strength of rocks using ultrasound

Abstract

One of the most significant techniques for evaluation of rock strength is by using the simple and economical Non-Destructive Technique (NDT). The ultrasound velocity of a rock mass is closely related to the intact rock properties and measuring the velocity in rock masses interrogates the rock structure and texture. The important influencing factors are rock type, mineralogical composition, rock texture, grain size, density, hardness, toughness, brittleness and drill ability index. Use of Empirical or analytical relationships among various physical and mechanical strength properties of materials to estimate the required engineering properties of rocks and other brittle materials of interest. The present work deals with the use of ultrasonic pulse velocity to predict mechanical properties of sandstone and concretes. Cylindrical specimens with length to diameter ratio of two were prepared for this study and were characterized based on their physico-mechanical properties. We have carried out ultrasonic pulse velocity (UPV) measurements and Uniaxial compressive strength (UCS) tests on large number of sandstone and concrete samples. Each specimen was tested by non destructive test and followed by uniaxial compression test to assess the mechanical properties.