DYNAMIC PHYSICAL PROPERTIES OF ROCK; PART I, THEORY AND PROCEDURE

THIS IS A SYSTEMATIC STUDY OF DYNAMIC TESTING, BOTH SONIC AND PULSE TECHNIQUES USED IN COMPUTING THE ELASTIC PHYSICAL PROPERTIES OF ROCK SAMPLES. IN THE SONIC METHOD, A CYLINDIRCAL ROCK SAMPLE IS CAUSED TO VIBRATE AT ITS FUNDAMENTAL LONGITUDINAL, TORSIONAL, AND TRANSVERSE VIBRATION. USING THE DIFFERENT MEASURED ROCK PARAMETERS, AND THE FREQUENCY OF VIBRATION, THE ELASTIC PHYSICAL PROPERTIES ARE COMPUTED. IN THE PULSE METHOD, LONGITUDINAL AND TRANSVERSE WAVES ARE PASSED THROUGH THE ROCK SAMPLE. THE TRANSVERSE WAVE IS GENERATED BY COMPLETELY CONVERTING A LONGITUDINAL WAVE TO A TRANSVERSE WAVE AT CRITICAL REFLECTION. FROM THE MEASURED TRAVEL TIME OF THE TWO WAVES IN THE ROCK SAMPLE, THE VELOCITY OF BOTH LONGITUDINAL AND TRANSVERSE WAVES IS COMPUTED FROM WHICH THE DYNAMIC ELASTIC PHYSICAL CONSTANTS ARE COMPUTED.