Abstract

NAMIN, F.Samimi; RINNE, M.  and  RAFIE, M.. Uncertainty determination in rock mass classification when using FRMR Software. J. S. Afr. Inst. Min. Metall. [online]. 2015, vol.115, n.11, pp.1073-1082. ISSN 2411-9717.  http://dx.doi.org/10.17159/2411-9717/2015/v115n11a12.

Rock mass classification systems constitute an integral part of empirical underground excavation design. One system that is commonly used to classify rock mass is the Rock Mass Rating, or RMR, system. The RMR system has evolved over time to better reflect the perceived influence of various rock mass factors on excavation stability. While the introduced modifications have enhanced the applicability of this classification system, there are still areas that cause potential ambiguity. The RMR system cannot deal with input data ambiguities, uncertainties, and vagueness. To deal with the uncertainty, a Fuzzy Rock Mass Rating (FRMR) has been developed. This study aims to describe the main concept of the fuzzy approach, which is implemented in the FRMR to classify rock mass. The FRMR considers the uncertainty associated with the input data (uncertain variables) used in rock mass classification. The Gol-e-Gohar (GEG) area 3 iron ore deposits in the south of Iran were chosen as the case study for investigating the applicability of FRMR. The results of this study show that the FRMR software tool can easily be used for rock mass classification, even if uncertain input parameters have been used. FRMR consists of three parts, each of which is suitable for certain conditions.

Keywords : rock mass classification; RMR; FRMR; geotechnical uncertainty; fuzzy logic.

        · text in English     · English ( pdf )