A Guide to Practical GEOTECHNICAL ENGINEERING in Africa

Table Of Contents

CONTENTS
PAGE
1.0 FRANKI AFRICA 1

2.0 GEOTECHNICAL INVESTIGATION 4
2.1 Guide for Planning a Geotechnical Investigation 5
2.2 Field Investigation Techniques 9
2.3 Geotechnical Engineering Laboratory Services 29
2.4 Site Investigation for Piling 31
2.5 Site Investigation for Ground Improvement 31
2.6 Site Investigation for Grouting 31
2.7 Site Investigation for Lateral Support 31
2.8 Applicable Norms / References & Bibliography 32

3.0 SOIL AND ROCK CLASSIFICATION AND DESIGN PARAMETERS 34
3.1 Notes on Soil Profiling 34
3.2 Notes on Rock Mass Description 41
3.3 Interpretation of Geotechnical Investigation and
Laboratory / in situ Testing Data 47
3.4 Permeability 68
3.5 Applicable Norms / References & Bibliography 69

4.0 PILING SYSTEMS 72
4.1 Factors Influencing the Selection of a Pile Type 72
4.2 Classification of Piling Systems 74
4.3 Summary Details of Piling Systems 75
4.4 Technical Details of Piling Systems 77
4.4.1 Franki Driven Cast-in-situ Piles 77
4.4.2 Driven Tube Piles 87
4.4.3 Precast Piles 93
4.4.4 Steel H-Piles 100
4.4.5 Ductile Piles 106
4.4.6 Auger Piles 109
4.4.7 Underslurry Piles 118
4.4.8 Continuous Flight Auger (CFA) Piles 127
4.4.9 Full Displacement Screwpiles 132
4.4.10 Forum Bored Piles 136
4.4.11 Oscillator Piles 141
4.4.12 Rotapiles 146
4.4.13 Micropiles 150
4.5 Pile Load Testing 154
4.5.1 Static Load Testing 154
4.5.2 Internal Jack Load Testing (O-Cell) 158
4.5.3 Dynamic Pile Testing 159
4.5.4 Load Test Results 162
4.5.5 Interpretation of Load Test Results 162
4.6 Pile Integrity Testing 162
4.6.1 Low Strain Impact Testing 163
4.6.2 Ultrasonic Testing 164
4.6.3 Thermal Integrity Profiling 167
4.7 Applicable Norms / References & Bibliography 168

5.0 GROUND IMPROVEMENT SYSTEMS 170
5.1 Factors Influencing the Selection of a Ground
Improvement Systems 170
5.2 Classification of Ground Improvement Systems 172
5.3 Summary Details of Ground Improvement Systems 173
5.4 Technical Details of Ground Improvement Systems 175
5.4.1 Vibratory Compaction 175
5.4.2 Dynamic Compaction 182
5.4.3 Vibratory Replacement 189
5.4.4 Dynamic Replacement 194
5.4.5 Driven Stone Columns 197
5.4.6 Rigid Inclusions 199
5.4.7 Soil Mixing 206
5.4.8 Accelerated Consolidation 213
5.5 Applicable Norms / References & Bibliography 216

6.0 GROUTING SYSTEMS 220
6.1 Factors influencing the Selection of a Grouting System 220
6.2 Classification of Grouting Systems 222
6.3 Summary Details of Grouting Systems 222
6.4 Technical Details of Grouting Systems 223
6.4.1 Permeation Grouting 223
6.4.2 Soil Fracture Grouting 226
6.4.3 Compaction Grouting 230
6.4.4 Jet Grouting 233
6.5 Applicable Norms / Reference & Bibliography 240

7.0 LATERAL SUPPORT SYSTEMS 242
7.1 Factors Influencing the Selection of a Lateral Support System 242
7.2 Classification of Lateral Support System 244
7.2.1 Embedded Walls 244
7.2.2 Reinforced Soils 246
7.3 Summary Details of Lateral Support Systems 248
7.4 Technical Details of Lateral Support Systems 250
7.4.1 Embedded Walls 250
7.4.2 Embedded Wall Support Systems 278
7.4.3 Reinforced Soils 287
7.5 Applicable Norms / References & Bibliography 295

8.0 TRENCHLESS TECHNOLOGY INSTALLATIONS 298
8.1 Pipe Jacking 298
8.2 Horizontal Auger Boring 300
8.3 Horizontal Directional Drilling (HDD) 300
8.4 Micro Tunnelling 302
8.5 Applicable Norms / References & Bibliography 303

9.0 UNDERPINNING 304
9.1 Old Foundation Removed and New Foundation Provided 306
9.2 New Footing Located Under the Existing One 307
9.3 Jack-piles Under the Existing Foundation 309
9.4 Piles Alongside the Existing Foundation 311
9.5 New Piled Foundation and Column 314
9.6 Piles Through Existing Foundation 314
9.7 Underpinning Using Micropiles 315
9.8 Underpinning Using Jet Grouting 316
9.9 Underpinning Using Compaction Grouting 317

10.0 PROBLEM SOILS AND THEIR FOUNDATION SOLUTIONS 318
10.1 Expansive Soils 319
10.2 Collapsible Soils 324
10.3 Soft Clays 327
10.4 Dolomites 329
10.5 Dispersive Soils 332
10.6 Liquefiable Soils 332
10.7 Applicable Norms / References & Bibliography 337

11.0 MARINE FOUNDATION ENGINEERING 338
11.1 Piling for Marine Structures 338
11.2 Earth Retention for Marine Structures 342
11.3 Soil Improvement for Marine Applications 352
11.4 Construction Methods for Quays and Jetties 353
11.5 Rehabilitation of Quays and Jetties 356
11.6 Applicable Norms / References & Bibliography 357

12.0 ENVIRONMENTAL ENGINEERING 358
12.1 Groundwater Monitoring 358
12.2 Monitoring of Surface Water 359
12.3 Containment / Remediation 360
12.4 Applicable Norms / References & Bibliography 363

13.0 LIMIT STATE DESIGN 364
13.1 Design for Serviceability 366
13.2 Design of Foundation Piles 366
13.3 Design for Retaining Structures and Ground Anchorage 367
13.4 Applicable Norms / References & Bibliography 369

14.0 DESIGN AIDS: PILING 370
14.1 Pile Capacity to Resist Compressive Load 370
14.2 Pile Capacity to Resist Uplift Load 390
14.3 Pile Capacity to Resist Lateral Load 392
14.4 The Design of Piles for Heaving Soil Conditions 396
14.5 Factors of Safety 399
14.6 Analysis and Design of Pile Groups 401
14.7 Settlement of a Single Pile and Pile Groups 404
14.8 Structural Design of Pile Shafts 413
14.9 Structural Design of Pile-capes 418
14.10 Applicable Norms / References & Bibliography 434

15.0 DESIGN AIDS: GROUND IMPROVEMENT 438
15.1 Vibro Compaction 438
15.2 Dynamic Compaction 440
15.3 Prefabricated Vertical Drains 444
15.4 Vibro Replacement 446
15.5 Rigid Inclusions 450
15.6 Soil Mixing 453
15.7 Applicable Norms / References & Bibliography 456

16.0 DESIGN AIDS: LATERAL SUPPORT 458
16.1 Geotechnical Design Parameters 458
16.2 Earth pressures 460
16.3 Water Pressures and Surcharge Loads 463
16.4 Embedded Walls 465
16.5 Reinforced Soils 473
16.6 Factors of Safety 478
16.7 Movements Associated with Excavations 479
16.8 Observational Method in Lateral Support Design 481
16.9 Applicable Norms / References & Bibliography 482

17.0 MONITORING AND INSTRUMENTATION 484
17.1 Measurement of Deformation 484
17.2 Measurement of Earth Pressure 486
17.3 Measurement of Pore Pressure 486
17.4 Measurement of Load in Structural Members 487
17.5 Measurement of Strain in Structural Members 488

18.0 QUALITY ASSURANCE AND SAFETY 490

19.0 REFERENCE INFORMATION 492
19.1 Normal Plant Clearance Requirements 492
19.2 Rig Dimensions: Bauer 495
19.3 Rig Dimensions: Liebherr 501
19.4 Rig Dimensions: Soilmec 507
19.5 Rig Dimensions: Comacchio 513
19.6 Rig Dimensions: Fiori 516
19.7 Rig Dimensions: Keller 518
19.8 Rig Dimensions: Franki 521
19.9 Rig Dimensions: Casagrande 523

INDEX 526

LIST OF SYMBOLS 531