Materiały konferencyjne SEP 2018

XXVII SCHOOL OF UNDERGROUNDMINING 2018 , Cracow, Poland GEOMECHANICAL EVALUATION (RMR COEFFICIENT) PARAMETER RANGE 1 UCS >250 MPa 100-250 MPa 50-100 MPa 25-50 MPa 1-25 MPa Points 15 12 7 4 0-2 2 RQD 90-100 % 75-90 % 50-75 % 25-50 % < 25% Points 15 12 7 4 0-2 3 Distance between discontinuities > 2 m 0.6-2 m 200-600 mm 60-200 mm < 60 mm Points 20 15 10 8 5 4 Character of discontinuities high rough low rough low weathered low rough high weathered slickensides cleavages Points 30 25 20 10 0 5 Watering (inflow to 10m roadway) 0 < 10 l/m 10-25 l/min 25-125 l/min > 125 l/min Points 15 10 7 4 0 6 Orientation of discontinuities most favourable favourable medium unfavourable most unfavourable Points 0 -2 -5 -10 -12 SUM TOTAL 100-81 80-61 60-41 40-21 20 CATEGORY I. II. III. IV. V. SUITABILITY FOR BOLTING most suitable suitable middle suitable unfavourable most unfavourable