Dyke G.P. A quantitative correlation between the mining rock mass rating and in-situ rock mass rating classification systems

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Engineering. — Johannesburg: University of the Witwatersrand, 2006. — 128 p.The three most common rock mass classification systems in use in the South African mining industry today are Bieniawski’s (1976) Geomechanics or RMR System, Barton et al.’s (1974) Q-System and Laubscher’s (1990) MRMR System respectively. Of these three systems, only the MRMR Classification System was developed specifically for mining applications, namely caving operations. In response to the increased use of the MRMR Classification System in the mining industry, and concerns that the MRMR System does not adequately address the role played by discontinuities, veins and cemented joints in a jointed rock mass, Laubscher and Jakubec introduced the In-Situ Rock Mass Rating System (IRMR) in the year 2000. A quantitative comparison of the MRMR and IRMR Classification Systems has been undertaken to determine a correlation between the two classification systems, the results of which indicate that there is not a major difference between the resultant rock mass rating values derived from the two Classification Systems. Therefore, although the IRMR System is more applicable to a jointed rock mass than the MRMR System, the MRMR System should not be regarded as redundant, as it still has a role to play as a mine design tool.Abstract
AcknowledgementsBackground to Rock Mass Classification
Objectives of the Study
Study Methodology
Structure of the Research Report
Literature Review
The Nature of Rocks and Rock Masses
The Philosophy of Quantitative Classification Systems
Implementation of Quantitative Classification Systems by the Mining Industry
The Evolution of Rock Mass Classification Systems
Literature Review Findings
Parametric and Geotechnical Databases
Scope of Study
The Parametric Database
The Geotechnical Database
Interpretation of Qualitative and Quantitative Analyses
MRMR Parametric Analysis
RMR Parametric Analysis
Qualitative Comparison of MRMR and IRMR Data Sets
Statistical Analysis of the MRMR and IRMR Database
Conclusions
Parametric Analysis
Quantitative Analysis
RecommendationsAppendices
MRMR Geotechnical Database
IRMR Geotechnical Database
Results of MRMR Parametric Analysis
Results of IRMR Parametric Analysis
MRMR and IRMR Classification System Sedimentary Rock Mass Data
MRMR and IRMR Classification System Igneous Rock Mass Data
MRMR and IRMR Classification System Metamorphic Rock Mass Data
Complete MRMR and IRMR Classification System Rock Data
Sedimentary Rock Mass Statistical Analysis Results
Igneous Rock Mass Statistical Analysis Results
Metamorphic Rock Mass Statistical Analysis Results
MRMR and IRMR Data Set Statistical Analysis Results