GENERATION AND PROPAGATION OF HAMMER TAPPING SOUND ON “RESPONSE SOUND PRESSURE PULSE INCLINATION METHOD”

Abstract

This is one of the studies aimed at quantitative evaluation of the indices for rock mass classification that deals with “judgment method by the hammer tapping”. In this study, we examined tapping test using specimens from an artificial rock and analyzed the tapping sound. We visualized that distribution of the sound pressure changes with time on the sound field around a hammer immediately after the tapping. As a result, we confirmed that the initial tapping sound had two propagation routes to the microphone as opposed to what was conceptualized until now. One is through the steel ball and the air afterwards, the other is through the air only.