Identification of rock jointing parameters by borehole imaging and interval geotechnical documentation of non-oriented drill cores

Abstract

The article presents a procedure for parametric characterization of jointing in rock mass based on borehole imaging and interval geotechnical documentation of non-oriented drill cores. The authors describe the involved objectives and the work sequence in borehole imaging of joints, the documentation of drill cores, the office analysis of data and the determination of angles and dip azimuths of joints. It is shown that in case of difficult geological conditions, higher rock pressure and over-jointing of rocks, mine support designs should be corrected using the geotechnical assessment of rock mass behavior and adjusted in Dips and Unwedge. Based on the bulk of the experimental research data, the procedure of borehole imaging and interval geotechnical documentation of non-oriented drill cores demonstrates efficiency in identification of jointing parameters in rock mass. This approach makes it possible to optimize design variables of structural components of mining systems and mine support patterns, to determine stability and quality of rock mass, as well as to calculate stability of potential sliding wedges. In the meanwhile, the cost of oriented core drilling is reduced and the data required for the calculation are successfully obtained. The authors highly appreciate the support of Evgeny Dorot, General Director of RSRS GmbH Railway Infrastructure Projects, and the Company’s experts in the development of guidelines on parametric characterization of rock mass jointing.The authors also acknowledge participation of A. R. Umarov, A. M. Yanbekov and Ch. V. Khazhyylay, Nguen Van Min, Post-Graduate Students and Project Engineers at the Research Center for Applied Geomechanics and Convergent Technologies in Mining, and V. N. Louchnikov, Group Head Geotechnical and Hydrogeology, POLYUS.