Relations Amony the Propagation Velocities of Elastic Waves, the Elastic Modulus and the Saturation of Rock Specimens (No. 1).

Abstract

It is important for the non-destructive testing carried out the measurement of wave propagation velocities to know the extent of variation of the propagation velocity of elastic waves in porous rocks by changing water content. We had been made an investigation of this problems.In this paper, we showed experimental results of the propagation velocity of elastic waves in rock specimens cured at the four circumstances which are the most easy curing method. They are (1) cooling in a desicator contained silicagel silicagel at room temparature after heating in the drying oven at 100-110°C above 24 hours, (2) drying in desicator contained silicagel to become a constant weight, (3) room dry, and (4) immersing in water during about a month to become a constant weight.On the experiment, the velocity dilatational wave Vpl and the velocity of shear wave Vps were measured by ultrasonic pulse method, and the velocity of longitudinal vibration VRl and the velocity of torsional vibration VRS were measured by resonant frequency method.Summary of this experiment are;(1) The propagation velocity of dilatational waves in racks cured at desicator with silicagel or at room dry measured by pulse method became the minimum, and the velocity increased when rock specimens were more saturated.(2) Velocities of the longitudinal vibration measured by resonant frequency method gradually decreased when rock specimens were saturated from dry state.(3) Both shear wave velocities measured by pulse method and resonant frequency method show a similar tendency of variation of the wave velocity with saturation of rocks.