Rock Mechanics Ground Control Research

Weak Rock Mass in Nevada Gold Mines: Behavior, Support Design and Performance

Many Nevada gold deposits are found in highly fractured, faulted, and argillised host rock (Brady et al., 2005) with Rock Mass Rating (RMR76) mostly ranging from 10 to 50 classified as weak to very weak rock under Bieniawski's (1976) rock mass classification system. As a consequence, underground mines experience hazardous and difficult to control ground conditions, resulting in many injuries and fatalities. The most common problems that we notice in weak rock mines are roof falling, rib spaling, pillar cracking and uncontrolled deformation, support failure etc.

Historically there has been very minimal or limited emphasis placed in addressing problems related to ground behavior, control, support design, and performance in weak rock masses in underground mines in the USA. With easy-to-mine resources depleting very fast, the mining operations are expanding to deeper and deeper horizons and experiencing even more difficult control ground conditions.

The current research work is aimed at addressing various ground control design issues in weak rock masses faced by underground mines operating in Nevada, and hence help improve safety of the mining operations in weak rock formations. The research work will cover a broad range of tasks ranging from extensive collection and creation of a database of case histories from field observations and field personnel experience, to use of advanced numerical simulation techniques in the laboratory. The objectives of this research will be achieved through empirical methods, field instrumentation and experimentation, laboratory testing and investigation, and advanced numerical modeling approaches.

The current research work also provides an excellent opportunity for graduate students to work on various aspects of ground control engineering techniques such as, review of ground control practices, field observations, data collection and measurement of rock parameters, use of instrumentation techniques, data interpretation and application, use of numerical simulation techniques for design in ground control, and laboratory investigation and testing of rock samples for key mechanical properties. Successful implementation of the current research project would allow for capacity building in ground control technology at the Mining Engineering Department of the University of Nevada, Reno, NV. Further, the research work will help develop much needed expertise in the field of ground control technology in weak rock mass and thus address serious shortage of ground control engineers in the USA.

This five-year research project is fully funded by NIOSH and received significant support from Nevada Mining Industry, particularly from Barrick Gold of North America and Newmont Mining Corporation, for facilitating field work and experimentation.

Prospective Ph.D./MS students please contact Dr. Kallu at