Abstract: After a discussion on the measurement of the compressive wave velocity in the formula of the rock mass integrity index as well as the representative wave velocity values, it is concluded that the rock mass integrity index estimation should be focused on the same type of rock mass with similar properties. The representative wave velocity in the rock mass in the engineering practice should be obtained by the statistical methods. It is unreasonable to use the maximum compressive wave velocity measured as the wave velocity in the intact and fresh rock sample. Once the mean value, maximum average value, minimum average value, median value and the standard deviation value are determined, the reliable compressive wave velocity value should be analyzed by its frequency distribution.

Key words: Rock Mass Integrity Index, Rock Sample Compressive Wave Velocity; , Rock Mass Compressive Wave Velocity, Testing and Measurement