2000 Volume 49 Issue 9 Pages 1042-1049
This is one of the studies aimed at quantitative evaluation of the indices for rock mass classification, which deals with “judgment method by the hammer tapping”. This method includes results from different test operators in order to be expressed qualitatively, for example “clear sound”, “sound slightly muddy”, and “sound remarkably muddy”. The problems of these indices are not quantitative. So, in the previous research we examined specimens (using the artificial rock) with various factors such as shape and dimension, boundary condition, tapping position, and the uneven surface by tapping with steel ball and analyzed the tapping sound. Results showed “response sound pressure pulse inclination” could quantitatively evaluate strength and deformation of a rock. In this report we examined specimens using metal (stainless steel, copper and aluminum) and nonmetal (vinyl chloride and natural rubber). Results confirmed that “response sound pressure pulse inclination” show difference of mechanical and physical properties of the specimens, and could identify parameters like the minimum size of the specimen with fixed tapping conditions.