MINE ENGINEERING ROCK MECHANICS

(…a personal view…)

W.G. Pariseau

Professor of Mining EngineeringDepartment of Mining Engineering

University of Utah, Salt Lake City, UT

ARMA WORKSHOPJune 26, 2010Park City, Utah

PAST ACHIEVEMENTS(that I have seen since 1960’s)

Where we are and how we got here…

Morning Panel Presentation

ARMA WORKSHOP

June 26, 2010

Park City, Utah

PAST PRACTICAL ACHIEVEMENTS: (laboratory testing, mine measurements, analysis, comparisons, demonstration…)

1. MINE FILL

2. IN SITU STRESS MEASUREMENT

3. STRESS ANALYSIS FOR DESIGN

4. ROCK SLOPE STABILITY

5. CABLE BOLTING AND VCR MINING

6. DRIFT AND FILLCRETE MINING

7. NUMERICAL METHODS FOR DESIGN

Mine Fill Research: lab testing +mine measurements+ FE modeling

SRC, USBM,Coeur d’Alene Mining District

Stress Measurement In Situ

Overcoring at the Kelly Block Cave Mine,Anaconda Co., Butte, MT

HI Cells

USBM BDG’s4-prong, 1-prong

Doorstoppers(4-gauge)

Stress Analysis for Design(the early years, for example)

• La Mecanique des Roches, J. Talobre, 1957

• Rock Mechanics and the Design of Structures in Rock, L. Obert and W. I. Duvall (1967).

• Elasticity, Fracture and Flow, J. C. Jaeger, 1969

• Rock Mechanics Principles, D.F. Coates (1970).

Mainly, stress concentration about holes of simple shape, using

results from elasticity theory, e.g., the problem of a circular hole in

plane strain or plane stress (Kirsch equations), other shapes using

complex variable theory – applied mathematics, pre-computer era.

Rock Slope Stability – Economics!

Rock Slope Engineering, E. Hoek and J. Bray, 1974

(wedge failures, joints, toppling, slip circles, drainage, blasting)

Rock Slope Stability – Economics! Guidelines for Open Pit Slope Design,

J. Read and P. Stacey (eds) 2009. (wedge failures, joints, toppling, slip circles, drainage, blasting, risk analysis)

Rock Slope Stability…2009

Blasting

Drainage

CABLE BOLTING & VCR MINING

INSTRUMENTATION and MINE MEASUREMENTS of DISPLACEMENTS

R=0.84

DRIFT& FILLCRETE MINING

75 ft span

instrumentation first and second pillar blasts

back fillcrete is holding nicelyTurquoise Ridge, Nevada, 2002

Numerical Methods for Design, i.e., FEM• Berkeley Pit, 1969

Numerical Methods for Design, i.e., FEMGalena Mine, 1972

Numerical Methods…• Continuum codes: FEM, BEM, FDM,

• Rock Block codes: DEM, NMM, DDA

(physical laws, kinematics, material laws)- equilibrium (static, dynamic) equations

- strain displacement equations- stress strain equations

NOTE: Continuum codes accommodate discontinuities and Rock Block codes

accommodate deformable blocks.

FUTURE NEEDS

(afternoon panel presentation)

Where do go from here?

ARMA WORKSHOP

June 26, 2010

Park City, Utah

Thank you!