Design Analysis in Rock Mechanics (PARISEAU, W G. 2006)
Preface xi
Acknowledgments xv
1 Introduction 1
1.1 A practical design objective 3
1.2 Problem solving 4
1.3 Units 5
1.4 Background information 6
Rock mechanics literature 6
Mechanical properties of rock 7
1.5 Problems 7
Basics 7
Review of stress 8
Review of strain and elasticity 10
2 Slope stability 15
2.1 Translational rock slope failures 18
Planar block slides 18
Saftey factor improvement 31
Wedge failures 38
2.2 Rotational slope failures 60
Remedial measures 68
Base failures 70
Toppling failures 72
2.3 Problems 73
Planar block slides 73
Wedge failures 78
Rotational slides 81
Dynamics, toppling 85
3 Shafts 87
3.1 Single unlined naturally supported shafts 87
Shaft wall stress concentration 88
Unlined circular shafts 89
Unlined elliptical shafts 94
Unlined rectangular shafts 101
Shaft wall strengths 113
3.2 Shaft wall support and liners 121
Shaft wall bolting 122
Circular shaft liners 130
Circular steel rings 140
3.3 Multiple naturally supported shafts 142
Circular shafts in a row 142
Shaft pillar safety 148
Two circular shafts of different diameter 153
Elliptical shafts in a row 155
Rectangular shafts in a row 158
3.4 Problems 162
Single, naturally supported shafts 162
Supported shafts, liners, bolts, rings 169
Multiple shafts 173
4 Tunnels 175
4.1 Naturally supported tunnels 175
Single tunnels 177
Single tunnel joints 184
Multiple tunnels 189
4.2 Tunnel support 194
Fixed steel sets 194
Pattern bolting – rock reinforcement 208
Combination support 212
Yieldable steel arches 218
Light segment liner 219
4.3 Problems 220
Naturally supported tunnels 220
Supported tunnels 221
Rock mass classification schemes, RQD 226
5 Entries in stratified ground 229
5.1 Review of beam analysis 229
Basic beam formulas 230
Important special cases 234
5.2 Softrock entries 243
Naturally supported roof 243
Bolted roof 255
Point anchored roof bolting 255
Distributed anchorage roof bolting 261
Roof trusses 264
5.3 Problems 266
Naturally supported roof 266
Bolted roof 268
6 Pillars in stratified ground 277
6.1 Pillars in a single seam 277
Tributary area, extraction ratio analysis 277
Size effect on strength 281
6.2 Pillars in dipping strata 289
Extraction ratio formulas for pillars in dipping seams 289
An unconventional Mohr’s circle representation 293
Generalized Mohr’s circle 298
Backfill effects on pillar safety factors 300
6.3 Pillars with joints 306
Flat seam pillars with joints 306
Dipping seam pillars with joints 310
6.4 Pillars in several seams 315
Columnized main entry pillars 315
Staggered chain entry pillars 321
6.5 Barrier pillars 324
6.6 Problems 329
7 Three-dimensional excavation-s 345
7.1 Naturally supported caverns and stopes 346
Spheroidal excavation-s 347
Cubical and brick-shaped excavation-s 356
7.2 Joints in cavern and stope walls 363
7.3 Tabular excavation-s 364
7.4 Cavern and stope support 366
Hardrock mine fill 367
Cable bolt support 386
7.5 Problems 390
3D Caverns 390
Back fill 391
Cable bolting 393
8 Subsidence 397
8.1 Chimneys 397
Chimney cave geometry 398
Caving rock flow 405
Chimney cave forces 407
Chimney cave water forces 417
Support near caving ground 421
8.2 Troughs 430
Limit of subsidence 431
Maximum subsidence 433
Critical width 433
NCB subsidence profile 435
Angle of draw and subsidence factor adjustments 440
NCB strain profile 444
Surface damage 451
Multipanel, multiseam subsidence 455
Alternative approaches to subsidence 461
8.3 Problems 461
Chimney caving 461
Combination support 464
Subsidence troughs 467
Appendix A: Background literature 469
A.1 Books about fundamentals of mechanics 469
A.2 Books about rock mechanics 470
A.3 Books containing rock properties 471
A.4 General sources of rock mechanics information 472
Appendix B: Mechanical properties of intact rock and joints 473
B.1 Elastic moduli of intact rock 474
Young’s modulus 474
Poisson’s ratio 477
Shear modulus 479
Anisotropy 480
B.2 Strength of intact rock 482
Tensile strength 482
Unconfined compressive strength 485
Compressive strength under confining pressure 495
Mohr–Coulomb strength 497
Hoek–Brown strength 499
Drucker–Prager strength 499
Nonlinear n-type strength 501
Compressive strength test data 501
B.3 Joint stiffness 507
Normal stiffness 508
Shear stiffness 509
B.4 Joint strength 509
B.5 Simple combination-s of intact rock and joints 512
Continuously jointed rock mass moduli 514
Discontinuously jointed rock mass moduli 518
Continuously jointed rock mass strengths 520
Discontinuously jointed rock mass strengths 523
Appendix C: Rock mass classification schemes for engineering 529
C.1 Rock quality designation 529
C.2 Terzaghi modified scheme 529
C.3 RSR, RMR, and Q 530
C.4 Comparison-s of Hp estimates 531
Appendix D: Some useful formulas 533
D.1 Stress 533
Normal and shear stress on a plane 535
Principal (normal) stresses 536
Principal shear stresses 537
Mohr’s circle 538
D.2 Strain 539
Strain rosettes 539
Small strain–displacement relation-s 541
D.3 Stress–strain relation-ships, Hooke’s law 541
Hooke’s law in one dimension – Young’s modulus and shear modulus 541
Hooke’s law in two-dimension-s – plane stress and plane strain 549
References 551
Index 557
