Estimation of stresses in a massive granite using laser ultra-sonic testing and stress memory effect

This paper addresses in-situ stress-estimation methods based on the Kaiser effect. The physical and mechanical properties of granite, diorite, granodiorite samples selected at different depth intervals core obtained from a wellbore were examined. ultimate uniaxial compressive strength, modulus elasticity, Poisson’s ratio rock determined using presses strain gauges. Also, local longitudinal shear wave velocities measured high-accuracy laser-ultrasonic system with view to assessing structure samples. Based resulting elastic velocity maps, no obvious discontinuities chosen. These undisturbed subjected compression their acoustic emission was simultaneously measured. In-situ stresses estimated results interpretation measurements. experimental compared numerical simulation. calculated ones is within range 0.81 1.11. means that laser ultrasonic make it possible effectively estimate in mass assess degree damage.