Soil Strength and Slope Stability, Second Edition presents the latest thinking and techniques in the assessment of natural and man-made slopes, and the factors that cause them to survive or crumble. Using clear, concise language and practical examples, the book explains the practical aspects of geotechnical engineering as applied to slopes and embankments. The new second edition includes a thorough discussion on the use of analysis software, providing the background to understand what the software is doing, along with several methods of manual analysis that allow readers to verify software results. The book also includes a new case study about Hurricane Katrina failures at 17th Street and London Avenue Canal, plus additional case studies that frame the principles and techniques described.
Slope stability is a critical element of geotechnical engineering, involved in virtually every civil engineering project, especially highway development. Soil Strength and Slope Stability fills the gap in industry literature by providing practical information on the subject without including extraneous theory that may distract from the application. This balanced approach provides clear guidance for professionals in the field, while remaining comprehensive enough for use as a graduate-level text. Topics include:
- Mechanics of soil and limit equilibrium procedures
- Analyzing slope stability, rapid drawdown, and partial consolidation
- Safety, reliability, and stability analyses
- Reinforced slopes, stabilization, and repair
The book also describes examples and causes of slope failure and stability conditions for analysis, and includes an appendix of slope stability charts. Given how vital slope stability is to public safety, a comprehensive resource for analysis and practical action is a valuable tool. Soil Strength and Slope Stability is the definitive guide to the subject, proving useful both in the classroom and in the field.
Table of Contents
Foreword ix
Preface xi
Chapter 1 Introduction 1
Summary 3
Chapter 2 Examples and Causes Of Slope Failures 5
2.1 Introduction 5
2.2 Examples of Slope Failure 5
2.3 The Olmsted Landslide 11
2.4 Panama Canal Landslides 12
2.5 The Rio Mantaro Landslide 12
2.6 Kettleman Hills Landfill Failure 13
2.7 Causes of Slope Failure 13
2.8 Summary 17
Chapter 3 Soil Mechanics Principles 19
3.1 Introduction 19
3.2 Total and Effective Stresses 20
3.3 Drained and Undrained Shear Strengths 21
3.4 Basic Requirements for Slope Stability Analyses 26
Chapter 4 Stability Conditions for Analysis 31
4.1 Introduction 31
4.2 End-of-Construction Stability 31
4.3 Long-Term Stability 32
4.4 Rapid (Sudden) Drawdown 32
4.5 Earthquake 33
4.6 Partial Consolidation and Staged Construction 33
4.7 Other Loading Conditions 34
4.8 Analysis Cases for Earth and Rockfill Dams 34
Chapter 5 Shear Strength 37
5.1 Introduction 37
5.2 Behavior of Granular Materials - Sand, Gravel, and Rockfill 37
5.3 Silts 52
5.4 Clays 57
5.5 Municipal Solid Waste 78
Chapter 6 Mechanics of Limit Equilibrium Procedures 81
6.1 Definition of the Factor of Safety 81
6.2 Equilibrium Conditions 82
6.3 Single Free-Body Procedures 82
6.4 Procedures of Slices: General 87
6.5 Procedures of Slices: Circular Slip Surfaces 87
6.6 Procedures of Slices: Noncircular Slip Surfaces 94
6.7 Procedures of Slices: Assumptions, Equilibrium Equations, and Unknowns 105
6.8 Procedures of Slices: Representation of Interslice Forces (Side Forces) 105
6.9 Computations with Anisotropic Shear Strengths 112
6.10 Computations with Curved Strength Envelopes 112
6.11 Finite Element Analysis of Slopes 112
6.12 Alternative Definitions of the Factor of Safety 113
6.13 Pore Water Pressure Representation 116
Chapter 7 Methods of Analyzing Slope Stability 125
7.1 Simple Methods of Analysis 125
7.2 Slope Stability Charts 126
7.3 Spreadsheet Software 128
7.4 Finite Element Analyses of Slope Stability 129
7.5 Computer Programs for Limit Equilibrium Analyses 130
7.6 Verification of Results of Analyses 132
7.7 Examples for Verification of Stability Computations 134
Chapter 8 Reinforced Slopes and Embankments 159
8.1 Limit Equilibrium Analyses with Reinforcing Forces 159
8.2 Factors of Safety for Reinforcing Forces and Soil Strengths 159
8.3 Types of Reinforcement 160
8.4 Reinforcement Forces 161
8.5 Allowable Reinforcement Forces and Factors of Safety 162
8.6 Orientation of Reinforcement Forces 163
8.7 Reinforced Slopes on Firm Foundations 164
8.8 Embankments on Weak Foundations 164
Chapter 9 Analyses for Rapid Drawdown 169
9.1 Drawdown during and at the End of Construction 169
9.2 Drawdown for Long-Term Conditions 169
9.3 Partial Drainage 177
9.4 Shear-Induced Pore Pressure Changes 177
Chapter 10 Seismic Slope Stability 179
10.1 Analysis Procedures 179
10.2 Pseudostatic Screening Analyses 182
10.3 Determining Peak Accelerations 184
10.4 Shear Strength for Pseudostatic Analyses 184
10.5 Postearthquake Stability Analyses 188
Chapter 11 Analyses of Embankments with Partial Consolidation of Weak Foundations 193
11.1 Consolidation During Construction 193
11.2 Analyses of Stability with Partial Consolidation 194
11.3 Observed Behavior of an Embankment Constructed in Stages 195
11.4 Discussion 197
Chapter 12 Analyses to Back-Calculate Strengths 201
12.1 Back-Calculating Average Shear Strength 201
12.2 Back-Calculating Shear Strength Parameters Based on Slip Surface Geometry 203
12.3 Examples of Back-Analyses of Failed Slopes 205
12.4 Practical Problems and Limitation of Back-Analyses 213
12.5 Other Uncertainties 214
Chapter 13 Factors of Safety and Reliability 215
13.1 Definitions of Factor of Safety 215
13.2 Factor of Safety Criteria 216
13.3 Reliability and Probability of Failure 217
13.4 Standard Deviations and Coefficients of Variation 217
13.5 Estimating Reliability and Probability of Failure 220
Chapter 14 Important Details of Stability Analyses 227
14.1 Location of Critical Slip Surfaces 227
14.2 Examination of Noncritical Slip Surfaces 233
14.3 Tension in the Active Zone 234
14.4 Inappropriate Forces in the Passive Zone 238
14.5 Other Details 241
14.6 Verification of Calculations 245
14.7 Three-Dimensional Effects 246
Chapter 15 Presenting Results of Stability Evaluations 249
15.1 Site Characterization and Representation 249
15.2 Soil Property Evaluation 249
15.3 Pore Water Pressures 250
15.4 Special Features 250
15.5 Calculation Procedure 250
15.6 Analysis Summary Figure 250
15.7 Parametric Studies 254
15.8 Detailed Input Data 257
15.9 Table of Contents 257
Chapter 16 Slope Stabilization and Repair 259
16.1 Use of Back-Analysis 259
16.2 Factors Governing Selection of Method of Stabilization 259
16.3 Drainage 260
16.4 Excavations and Buttress Fills 263
16.5 Retaining Structures 264
16.6 Reinforcing Piles and Drilled Shafts 267
16.7 Injection Methods 269
16.8 Vegetation 269
16.9 Thermal Treatment 270
16.10 Bridging 270
16.11 Removal and Replacement of the Sliding Mass 271
Appendix A Slope Stability Charts 273
Appendix B Curved Shear Strength Envelopes Forfully Softened Shear Strengths and Their Impact on Slope Stability Analyses 289
References 295
Index 309
