Numerical Analysis and Modelling in Geomechanics

✍ Scribed by John W. Bull

• Year: 2003
• Tongue: English
• Leaves: 397
• Edition: 1
• Category: Library

✦ Synopsis

In geomechanics, existing design methods are very much dependent upon sophisticated on-site techniques to assess ground conditions. This book describes numerical analysis, computer simulation and modelling that can be used to answer some highly complex questions associated with geomechanics. The contributors, who are all international experts in the field, also give insights into the future directions of these methods.Numerical Analysis and Modelling in Geomechanics will appeal to professional engineers involved in designing and building both onshore and offshore structures, where geomechanical considerations may well be outside the usual codes of practice, and therefore specialist advice is required. Postgraduate researchers, degree students carrying out project work in this area will also find the book an invaluable resource.

✦ Table of Contents

Book Cover......Page 1
Half-Title......Page 2
Title......Page 3
Copyright......Page 4
Contents......Page 5
Figures......Page 7
Tables......Page 14
Contributors......Page 16
Preface......Page 18
Introduction......Page 20
Camouflet characteristics......Page 22
Camouflet size and material requirements......Page 25
Deflection model......Page 27
Finite element program......Page 28
Camouflet determination......Page 30
Depth of the zones above the void......Page 31
Discussion of the numerical results......Page 34
Conclusion......Page 40
References......Page 42
Compressed air tunnelling......Page 45
Factors affecting air losses......Page 46
Permeability of the ground to air......Page 47
Current practice in designing for compressed air......Page 48
Deficiencies of the current practice......Page 49
Analysis of air flow through tunnel face......Page 51
Governing equations......Page 52
Numerical solution......Page 54
Analysis of the air losses from tunnel perimeter walls......Page 55
Parameter identification......Page 57
Genetic algorithm......Page 58
Case study......Page 59
Numerical analysis and comparison......Page 61
Theory of shear strength for unsaturated soils......Page 65
Apparatus......Page 66
TEST SERIES 1: INCREASING AIR PRESSURE......Page 67
TEST SERIES 2: INCREASING SUCTION......Page 69
Discussion of the results......Page 71
Conclusion......Page 75
References......Page 78
Introduction......Page 80
Boundary value problem......Page 81
General finite element model for wave-seabed-structure interaction (GFEM-WSSI)......Page 84
Wave-seabed-pipe interaction......Page 86
Effects of soil characteristics......Page 88
Effects of geometry of the pipe......Page 93
Effects of cover layer......Page 97
Wave-seabed-caisson interaction......Page 105
Contours of pore pressure distribution......Page 106
Effects of cross-anisotropic soil behaviour......Page 108
Effects of basic soil characteristics......Page 110
Effects of geometry of caisson and rubble mound......Page 116
References......Page 120
Abstract......Page 123
Introduction......Page 124
Theory of water flow in unsaturated soils......Page 127
Theory of shear strength for unsaturated soils......Page 130
The mid-levels on Hong Kong island......Page 131
Numerical experiments using the finite element method......Page 132
Influence of rainfall Intensity......Page 134
Influence of rainfall duration......Page 138
Influence of saturated water permeability......Page 142
Conclusions......Page 146
References......Page 148
Impact hammers......Page 151
Vibratory hammers......Page 154
Sensitivity of humans and of buildings......Page 155
Objectives of the current study......Page 156
Element verification......Page 158
Infinite elements......Page 160
Impact hammers......Page 163
Stage 1......Page 164
Stage 2......Page 165
Stage 3......Page 166
Impact driving at the M66......Page 167
Impact driving at Flitwick, Bedfordshire......Page 168
Vibrodrivers......Page 169
Computational procedure......Page 172
Calibration of the vibrodriver model......Page 173
Vibrodriving at Flitwick......Page 174
Ground wave modelling and applications......Page 175
Rectangular steel portal frame......Page 178
Plane brickwork wall......Page 179
Buried gas main......Page 180
Conclusions......Page 181
Acknowledgements......Page 183
References......Page 184
Introduction......Page 187
An inverse method for elastic back analysis......Page 188
Direct solution technique......Page 190
Probabilistic back analysis......Page 191
Elastic back analysis......Page 197
Elasto-plastic calculations......Page 201
Tunnel characteristics......Page 207
Model for the analysis......Page 208
Evaluation of the shear strength parameters......Page 212
Evaluation of the viscosity coefficient......Page 216
Conclusions......Page 217
References......Page 218
Introduction......Page 220
Model identification......Page 221
Formulation of extended Bayesian method......Page 223
Uncertainty evaluation of model parameters......Page 224
General......Page 225
Selection of model parameters......Page 226
Treatment of measured displacements......Page 228
Data preparation......Page 229
Sensitivity analysis......Page 230
Case study......Page 231
Measurement......Page 233
Selection of model parameters......Page 234
Model identification......Page 235
Parameter estimation......Page 237
Concluding remarks......Page 239
References......Page 240
Introduction......Page 242
Hazard analysis......Page 243
Seismic sources......Page 244
Earthquake catalogue......Page 246
Attenuation relationships......Page 247
Identification of the response spectra and accelerograms for the analysis......Page 248
1D model......Page 249
The BESOIL program......Page 254
The QUAD4M program......Page 257
Some characteristics of The Umbria-Marche seismic sequence......Page 260
Geologic and geomorphologic overview and sample area selection......Page 261
Analysis......Page 263
Response parameters......Page 265
CESI VILLAGE......Page 267
COLFIORITO VILLAGE......Page 268
Practical application......Page 271
References......Page 272
Introduction......Page 277
Equations of motion......Page 278
Discretisation of the physical domain......Page 280
Discretisation of the wave equation......Page 282
Issues specific to the implementation......Page 284
Ground shaking scenario in Catania (Sicily, Italy)......Page 286
Influence of a massive structure on the free surface ground motion......Page 294
Conclusions......Page 296
Acknowledgements......Page 297
References......Page 298
Numerical methods for pile group analysis......Page 302
Load distribution in pile groups......Page 306
PGROUPN method of analysis......Page 309
Soil domain......Page 310
Solution of the system......Page 311
Cohesionless soil......Page 312
Extension to non-linear soil behaviour......Page 313
Numerical results......Page 314
Single pile response......Page 315
Pile group settlement......Page 316
Axial load distribution......Page 318
Lateral load distribution......Page 320
Pile group under general loading conditions......Page 321
Selection of soil parameters......Page 322
North London railway viaduct......Page 325
Comparison with field test data by O’Neill et al. (1982)......Page 327
Comparison with field test data by Briaud et al. (1989)......Page 329
Comparison with field test data by Huang et al. (2001)......Page 332
Final remarks......Page 335
Acknowledgements......Page 337
References......Page 338
Introduction......Page 341
Reservoir compaction and surface subsidence......Page 342
A problem of scale......Page 345
Casing damage......Page 347
Mechanics of porous media......Page 348
Linear momentum balance......Page 349
The concept of effective stress......Page 350
Variational forms of governing equations......Page 352
Finite element discretization......Page 353
Linearization of variational forms......Page 354
Linear constitutive theory......Page 356
Nonlinear, elastic-plastic constitutive model......Page 358
Constitutive model input data requirements......Page 362
Coupling between pore pressure and rock deformation......Page 363
Initial geostatic field......Page 365
Modeling casing damage and failure under shearing......Page 366
Historical well failures......Page 368
Field-scale model......Page 370
Simulated field operational history......Page 372
Computational results......Page 373
Field-scale model......Page 374
Wellbore scale results......Page 375
Tool length......Page 382
Permanently bent tubing......Page 384
Mitigation of well damage......Page 385
References......Page 387
Index......Page 394

✦ Subjects

Горно-геологическая отрасль;Физика пород, пластов, массивов;Механика горных пород;