Bieniawski (1976) published the details of a rock mass
classification called the Geomechanics Classification or the Rock
Mass Rating (RMR) system.
Bieniawski’s RMR system is one of the oldest of the often so-
called ‘recent’ systems. The system has been developed in South
Africa for underground mining. The system is based on a
combination of six parameters. Each parameter is expressed in a
point rating and the final RMR ranges between 0 (very poor rock for
tunneling) to 100 (very good rock for tunneling).