Principles of Geotechnical Engineering

Cover......Page 1
Half Title......Page 4
Title......Page 6
Statement......Page 7
Copyright......Page 8
Dedication......Page 9
Preface......Page 11
About the Authors......Page 15
Contents......Page 17
1.2 Geotechnical Engineering Prior to the 18th Century......Page 27
1.3 Preclassical Period of Soil Mechanics (1700–1776)......Page 31
1.5 Classical Soil Mechanics—Phase II (1856–1910)......Page 32
1.6 Modern Soil Mechanics (1910–1927)......Page 33
1.7 Geotechnical Engineering after 1927......Page 34
1.8 End of an Era......Page 38
References......Page 39
2.2 Rock Cycle and the Origin of Soil......Page 41
2.3 Rock-Forming Minerals, Rock and Rock Structures......Page 52
2.4 Soil-Particle Size......Page 63
2.5 Clay Minerals......Page 65
2.6 Specific Gravity (Gs)......Page 73
2.7 Mechanical Analysis of Soil......Page 74
2.8 Particle-Size Distribution Curve......Page 81
2.9 Particle Shape......Page 87
2.10 Summary......Page 88
Problems......Page 89
Critical Thinking Problem......Page 91
References......Page 92
3.2 Weight–Volume Relationships......Page 93
3.3 Relationships among Unit Weight, Void Ratio, Moisture Content, and Specific Gravity......Page 96
3.4 Relationships among Unit Weight, Porosity, and Moisture Content......Page 100
3.5 Various Unit Weight Relationships......Page 101
3.6 Relative Density......Page 107
3.7 Comments on emax and emin......Page 110
3.8 Correlations Between emax, emin, emax ─ emin, and Median Grain Size (D50)......Page 113
Problems......Page 116
References......Page 118
4.2 Liquid Limit (LL)......Page 120
4.3 Plastic Limit (PL)......Page 127
4.4 Shrinkage Limit (SL)......Page 129
4.5 Liquidity Index and Consistency Index......Page 135
4.6 Activity......Page 136
4.7 Plasticity Chart......Page 138
4.8 Soil Structure......Page 140
4.9 Summary......Page 145
Critical Thinking Problems......Page 146
References......Page 147
5.1 Introduction......Page 149
5.2 Textural Classification......Page 150
5.4 AASHTO Classification System......Page 152
5.5 Unified Soil Classification System......Page 156
5.6 Comparison between the AASHTO and Unified Systems......Page 158
Problems......Page 168
Critical Thinking Problem......Page 170
References......Page 171
6.2 Compaction—General Principles......Page 172
6.3 Standard Proctor Test......Page 173
6.4 Factors Affecting Compaction......Page 176
6.6 Empirical Relationships......Page 180
6.7 Structure of Compacted Clay Soil......Page 187
6.8 Effect of Compaction on Cohesive Soil Properties......Page 189
6.9 Field Compaction......Page 192
6.10 Specifications for Field Compaction......Page 197
6.11 Determination of Field Unit Weight of Compaction......Page 198
6.12 Compaction of Organic Soil and Waste Materials......Page 205
6.14 Special Compaction Techniques......Page 208
Problems......Page 218
Critical Thinking Problem......Page 220
References......Page 221
7.2 Bernoulli’s Equation......Page 224
7.3 Darcy’s Law......Page 226
7.4 Hydraulic Conductivity......Page 228
7.5 Laboratory Determination of Hydraulic Conductivity......Page 230
7.6 Relationships for Hydraulic Conductivity—Granular Soil......Page 237
7.7 Relationships for Hydraulic Conductivity—Cohesive Soils......Page 244
7.8 Directional Variation of Permeability......Page 249
7.9 Equivalent Hydraulic Conductivity in Stratified Soil......Page 251
7.10 Permeability Test in the Field by Pumping from Wells......Page 256
7.11 In Situ Hydraulic Conductivity of Compacted Clay Soils......Page 258
7.12 Summary and General Comments......Page 262
Critical Thinking Problem......Page 266
References......Page 267
8.2 Laplace’s Equation of Continuity......Page 269
8.3 Continuity Equation for Solution of Simple Flow Problems......Page 271
8.4 Flow Nets......Page 275
8.5 Seepage Calculation from a Flow Net......Page 276
8.6 Flow Nets in Anisotropic Soil......Page 280
8.7 Mathematical Solution for Seepage......Page 282
8.8 Uplift Pressure under Hydraulic Structures......Page 284
8.9 Seepage through an Earth Dam on an Impervious Base......Page 285
8.10 L. Casagrande’s Solution for Seepage through an Earth Dam......Page 288
8.11 Filter Design......Page 290
Problems......Page 293
References......Page 296
9.2 Stresses in Saturated Soil without Seepage......Page 297
9.3 Stresses in Saturated Soil with Upward Seepage......Page 302
9.5 Seepage Force......Page 306
9.6 Heaving in Soil Due to Flow around Sheet Piles......Page 311
9.7 Use of Filters to Increase the Factor of Safety against Heave......Page 316
9.8 Effective Stress in Partially Saturated Soil......Page 319
9.9 Capillary Rise in Soils......Page 320
9.10 Effective Stress in the Zone of Capillary Rise......Page 322
9.11 Summary and General Comments......Page 325
Problems......Page 326
References......Page 330
10.1 Introduction......Page 331
10.2 Normal and Shear Stresses on a Plane......Page 332
10.3 The Pole Method of Finding Stresses along a Plane......Page 336
10.4 Stresses Caused by a Point Load......Page 338
10.5 Vertical Stress Caused by a Vertical Line Load......Page 340
10.6 Vertical Stress Caused by a Horizontal Line Load......Page 343
10.7 Vertical Stress Caused by a Vertical Strip Load (Finite Width and Infinite Length)......Page 344
10.8 Linearly Increasing Vertical Loading on an Infinite Strip......Page 349
10.9 Vertical Stress Due to Embankment Loading......Page 352
10.10 Vertical Stress below the Center of a Uniformly Loaded Circular Area......Page 356
10.11 Vertical Stress at Any Point below a Uniformly Loaded Circular Area......Page 357
10.12 Vertical Stress Caused by a Rectangularly Loaded Area......Page 361
10.13 Influence Chart for Vertical Pressure......Page 368
10.14 Summary and General Comments......Page 371
Problems......Page 372
Critical Thinking Problem......Page 376
References......Page 378
11.1 Introduction......Page 379
11.2 Contact Pressure and Settlement Profile......Page 380
11.3 Relations for Elastic Settlement Calculation......Page 382
11.4 Fundamentals of Consolidation......Page 390
11.5 One-Dimensional Laboratory Consolidation Test......Page 394
11.6 Void Ratio–Pressure Plots......Page 396
11.7 Normally Consolidated and Overconsolidated Clays......Page 400
11.8 General Comments on Conventional Consolidation Test......Page 402
11.9 Effect of Disturbance on Void Ratio–Pressure Relationship......Page 404
11.10 Calculation of Settlement from One-Dimensional Primary Consolidation......Page 405
11.11 Correlations for Compression Index (Cc)......Page 407
11.12 Correlations for Swell Index (Cs)......Page 409
11.13 Secondary Consolidation Settlement......Page 415
11.14 Time Rate of Consolidation......Page 417
11.15 Determination of Coefficient of Consolidation......Page 426
11.16 Calculation of Consolidation Settlement under a Foundation......Page 434
11.17 A Case History—Settlement Due to a Preload Fill for Construction of Tampa VA Hospital......Page 436
11.18 Methods for Accelerating Consolidation Settlement......Page 440
11.19 Precompression......Page 442
11.20 Summary and General Comments......Page 446
Problems......Page 447
Critical Thinking Problem......Page 452
References......Page 453
12.2 Mohr–Coulomb Failure Criterion......Page 455
12.3 Inclination of the Plane of Failure Caused by Shear......Page 457
12.5 Direct Shear Test......Page 459
12.6 Drained Direct Shear Test on Saturated Sand and Clay......Page 464
12.7 General Comments on Direct Shear Test......Page 466
12.8 Triaxial Shear Test-General......Page 471
12.9 Consolidated-Drained Triaxial Test......Page 472
12.10 Consolidated-Undrained Triaxial Test......Page 481
12.11 Unconsolidated-Undrained Triaxial Test......Page 487
12.12 Unconfined Compression Test on Saturated Clay......Page 489
12.13 Empirical Relationships between Undrained Cohesion (cu) and Effective Overburden Pressure (σ'о)......Page 490
12.14 Sensitivity and Thixotropy of Clay......Page 492
12.15 Strength Anisotropy in Clay......Page 495
12.16 Vane Shear Test......Page 496
12.18 Shear Strength of Unsaturated Cohesive Soils......Page 502
12.19 Stress Path......Page 505
12.20 Summary and General Comments......Page 510
Problems......Page 511
Critical Thinking Problem......Page 514
References......Page 515
13.2 At-Rest, Active, and Passive Pressures......Page 517
13.3 Earth Pressure At-Rest......Page 520
13.4 Earth Pressure At-Rest for Partially Submerged Soil......Page 522
13.5 Rankine’s Theory of Active Pressure......Page 525
13.6 Theory of Rankine’s Passive Pressure......Page 527
13.7 Yielding of Wall of Limited Height......Page 529
13.8 Rankine Active and Passive Pressure with Sloping Backfill......Page 530
13.9 Diagrams for Lateral Earth-Pressure Distribution against Retaining Walls......Page 532
13.10 Coulomb’s Active Pressure......Page 544
13.11 Graphic Solution for Coulomb’s Active Earth Pressure......Page 547
13.13 Active Force on Retaining Walls with Earthquake Forces......Page 553
13.14 Common Types of Retaining Walls in the Field......Page 562
13.15 Summary and General Comments......Page 569
Problems......Page 571
Critical Thinking Problem......Page 574
References......Page 575
14.2 Retaining Walls with Friction......Page 576
14.3 Properties of a Logarithmic Spiral......Page 578
14.4 Procedure for Determination of Passive Earth Pressure (Pp)—Cohesionless Backfill......Page 580
14.5 Coefficient of Passive Earth Pressure (Kp)......Page 582
14.6 Caquot and Kerisel Solution for Passive Earth Pressure (Granular Backfill)......Page 586
14.7 Passive Force on Walls with Earthquake Forces......Page 589
14.8 Braced Cuts—General......Page 591
14.9 Determination of Active Thrust on Bracing Systems of Open Cuts—Granular Soil......Page 593
14.11 Pressure Variation for Design of Sheetings, Struts, and Wales......Page 595
Problems......Page 600
References......Page 602
15.1 Introduction......Page 603
15.2 Factor of Safety......Page 605
15.3 Stability of Infinite Slopes......Page 606
15.4 Infinite Slope with Steady-state Seepage......Page 609
15.5 Finite Slopes—General......Page 612
15.6 Analysis of Finite Slopes with Plane Failure Surfaces (Culmann’s Method)......Page 613
15.7 Analysis of Finite Slopes with Circular Failure Surfaces—General......Page 616
15.8 Mass Procedure—Slopes in Homogeneous Clay Soil with Ø = 0......Page 617
15.9 Recent Developments on Critical Circle of Clay Slopes (Ø = 0)......Page 624
15.10 Mass Procedure—Slopes in Homogeneous c' ― Ø' Soil......Page 625
15.11 Ordinary Method of Slices......Page 632
15.12 Bishop’s Simplified Method of Slices......Page 640
15.13 Stability Analysis by Method of Slices for Steady-State Seepage......Page 642
15.14 Solutions for Steady State Seepage......Page 643
15.15 A Case History of Slope Failure......Page 654
15.16 Morgenstern’s Method of Slices for Rapid Drawdown Condition......Page 658
15.17 Fluctuation of Factor of Safety of Slopes in Clay Embankment on Saturated Clay......Page 660
Problems......Page 664
References......Page 668
16.1 Introduction......Page 670
16.2 Ultimate Soil-Bearing Capacity for Shallow Foundations......Page 671
16.3 Terzaghi’s Ultimate Bearing Capacity Equation......Page 673
16.4 Effect of Groundwater Table......Page 677
16.5 Factor of Safety......Page 678
16.6 General Bearing Capacity Equation......Page 681
16.7 A Case History for Evaluation of the Ultimate Bearing Capacity......Page 685
16.8 Ultimate Load for Shallow Foundations Under Eccentric Load......Page 689
16.9 Bearing Capacity of Sand Based on Settlement......Page 694
16.10 Plate-Load Test......Page 696
Problems......Page 699
References......Page 702
17.1 Introduction......Page 704
17.2 Planning for Soil Exploration......Page 705
17.3 Boring Methods......Page 706
17.4 Common Sampling Methods......Page 710
17.6 Correlations for Standard Penetration Test......Page 715
17.7 Other In Situ Tests......Page 720
17.8 Rock Coring......Page 725
17.10 Summary......Page 727
Problems......Page 729
References......Page 730
Appendix – A: A Generalized Case for Rankine Active and Passive Pressure—Granular Backfill......Page 732
Answers to Selected Problems......Page 740
Index......Page 748