SHEAR STRENGTH AND PROPAGATION OF SEISMIC WAVE DURING ROCK JOINT SHEAR TEST UNDER CONSTANT PRESSURE AND CONSTANT DILATANCY

Abstract

Through the long term running research conducted by the prime author, it has been clarified that, when seismic wave propagated through rock joints, the change of amplitude showed more sensitive than that of propagating velocity. Basing on this observation, the authors carried out the measurement of the velocity and amplitude of propagating wave during the rock joint shear test. It was confirmed that the monitoring by means of the change of amplitude of propagating wave could show the progress of loosening during excavation. The final objective of the research is to estimate the magnitude of loosening phenomenon in quantitative manner which is essential in rock tunneling.