A G H 2010 Profesor Zdzis ł aw Bieniawski 1

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“Idea” #1 Badania polowe w Geoinżynierii 4

Plate jacking tests 5

Another well-known in situ test Large Flat Jack (LFJ) test 6

Other types of large in situ tests Tri-axial block test Coal mine pillar test 7

RMR versus Rock Mass Modulus E m from penetrometer tests (Galera 2005)

RMR versus ratio E mass /E intact (penetrometer data after Galera 2005)

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Rock mass deformation Modulus (GPa) E MASS = 10 [(RMR - 10)/40] and for RMR > 50: E MASS = 2 RMR – 100 Latest correlations (Galera 2008): E MASS = 147 e [(RMR - 100)/24] RMR Alternatively for RMR < 50: E MASS = 0.09 RMR and for RMR > 50: E MASS = 0.09 RMR (RMR- 50 ) (RMR- 50 ) 2 Correlation coefficient: R =

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Rock Mass Modulus versus RMR and Q (check correlation)

14 Rock Mass Strength Kalamaras, 1995

Rock mass deformation Modulus Another correlation by Galera 2008: E MASS = E intact e [(RMR - 100)/36] For full range of RMR 15

Rock mass strength (MPa)  MASS =  c intact e [(RMR - 100)/24] Kalamaras [1995] As per the last correlation of Galera 2008: E MASS = E intact e [(RMR - 100)/36] it follows: E M  M E i  c 2/3 16

concerning Rock Mass Strength 17 This expression: E M  M E i  c is preferable to the Hoek – Brown criterion in which: m/m i = e [(RMR - 100)/28] and s = e [(RMR - 100)/9] Due to uncertainty of m i values and equating RMR with GSI 2/3 W a r n i n g !

Example of needed Rock Mechanics focus Mechanized excavation in Mining and Tunneling deserves special attention in Rock Mechanics today Consider the case of TBM tunneling: determination of rock mass excavability (TBM rate of advance) 18

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World Record! The largest Tunnel Boring Machine (T B M) cannot function without Rock Mechanics! 23

Ratings for Rock Mass Excavability index (RME): Input parameters Uniaxial compressive strength of intact rock [0 – 25 points]  ci (MPa) < > 180 Ratings Drillability – Drilling Rate Index [0 – 15 points] DRI> < 40 Ratings Discontinuities at excavation front [0 – 40 points] HomogeneityNo. of joints per metreOrientation versus tunnel axis HomogeneousMixed >30PerpendicularObliqueParallel Ratings Stand up Time [0 – 25 points] Hours< > 192 Ratings Groundwater inflow [0 – 5 points] litres/sec> < 10 Ratings01245

Roof Span versus Stand Up Time as function of RMR and Q

Correlation between Rock Mass Excavability index (RME) and Average Rate of Advance (m/day) for Double Shield TBMs 26

Double Shield TBMs σ ci < 45 MPa

“Idea” #3 Maszyny tarczowe T B M 28

Badania polowe w geoinżynierii Profesor Profesor Z.T. Bieniawski A G H 2010 A G H 2010 Kraków Dziękuję za słuchanie