Soil Properties and their Correlations

Mike Carter is a civil and geotechnical engineer whose experience ranges from the practical, including site-based supervision of construction work, to the analytical, including the preparation of geotechnical design manuals and computer-based methods for consulting engineers. He has worked both in the UK and overseas; for consulting engineers, a contractor, a specialist site investigation contractor and as a university lecturer. In terms of engineering complexity, projects he has worked on have varied from the basic, such rural roads in East Africa and India, to the large and complex, such as the construction of an artificial island for Macau International Airport. He has also been involved in the analysis and rectification of numerous earthworks failures and has worked as a lecturer and trainer in the UK, Indonesia and Sri Lanka. He is the author of three books on geotechnical engineering.Dr Bentley is an Engineering Geologist. During his long academic career at Cardiff University he has acted as a consultant to many large UK companies including the Department of the Environment (UK). He has also been retained as a consultant to the Departments of Public Works in Brunei and Saudi Arabia. He has supervised 12 PhD and over 60 MSc students; most of the PhD research topics were collaborative with industry. He has published 110 technical papers. Highlights of his research work include the first edition of the textbook 'Correlation of Soil Properties' which was adopted by many consultancy firms as a standard reference book. Also the visualisation software, 'STRATA', which was successfully commercialised and sold into over 100 companies in 12 countries worldwide.

• Preface xAcknowledgements xiiList of Symbols xiiiList of Property Values and Correlations in the Tables and Figures xx1 Commonly Measured Properties 11.1 Moisture Content 21.1.1 Test Methods 21.2 Grading 31.2.1 Test Methods 41.3 Plasticity 71.3.1 Test Methods 71.4 Specific Gravity of Soil Particles 101.4.1 Test Method 101.5 Soil Density 111.5.1 Test Methods 121.6 Permeability 161.6.1 Test Methods 171.7 Consolidation 191.7.1 Test Method 201.8 Shear Strength 211.8.1 Test Methods 221.8.2 Choice of Shear Strength Test 271.9 Standard Compaction Test 271.9.1 Test Method 271.10 California Bearing Ratio 301.10.1 Test Method 301.11 Other Properties 321.11.1 Swelling Potential 321.11.2 Frost Susceptibility 321.11.3 Combustible Content 33References 332 Grading and Plasticity 342.1 Grading 342.1.1 The influence of Grading on Soil Properties 352.1.2 Standard Grading Divisions 362.2 Plasticity 382.2.1 Consistency Limits 412.2.2 Development of the Liquid and Plastic Limit Tests 422.2.3 Plasticity Test Results and Plasticity Descriptions 432.2.4 The Shrinkage Limit Test 432.2.5 Consistency Limits as Indicators of Soil Behaviour 452.2.6 Limitations of the Use of Plasticity Limits 47References 473 Density 493.1 Density in the Context of Soils 493.1.1 Density Relationships 503.1.2 Typical Natural Density Values 533.2 Compacted Density 533.2.1 Typical Compacted Density Values 543.2.2 Quick Estimates of Maximum Dry Density and Optimum Moisture Content 553.3 Relative Density 593.3.1 Field Measurement of Relative Density 593.3.2 SPT Correction Factors 603.3.3 Other Dynamic Cone Tests 643.3.4 Static Cone Tests 65References 664 Permeability 684.1 Effects of Soil Macro]Structure 694.2 Typical Values 694.3 Permeability and Grading 71References 735 Consolidation and Settlement 745.1 Compressibility of Clays 755.1.1 Compressibility Parameters 755.1.2 Settlement Calculations Using Consolidation Theory 785.1.3 Settlement Calculations Using Elastic Theory 795.1.4 Typical Values and Correlations of Compressibility Coefficients 815.1.5 Settlement Corrections 845.2 Rate of Consolidation of Clays 865.3 Secondary Compression 885.4 Settlement of Sands and Gravels 925.4.1 Methods Based on Standard Penetration Tests 935.4.2 Methods Based on Plate Bearing Tests 1015.5 Assessment of Settlement Parameters from Static Cone Penetration Testing 1025.5.1 Coefficient of Volume Compressibility 1025.5.2 Coefficient of Consolidation 103References 1056 Shear Strength 1076.1 Stresses Within a Material 1086.1.1 The Mohr Diagram 1086.1.2 Relationships of Stresses at a Point 1086.2 Shear Strength in Soils 1136.3 The Choice of Total or Effective Stress Analysis 1166.3.1 The Choice in Practice 1166.4 Peak, Residual and Constant]Volume Shear Strength 1186.5 Undrained Shear Strength of Clays 1196.5.1 Consistency and Remoulded Shear Strength 1196.5.2 Consistency and Undisturbed Shear Strength 1206.5.3 Estimates Using the Standard Penetration Test 1266.5.4 Estimates Using Dynamic Cone Tests 1286.5.5 Estimates Using Static Cone Tests 1306.6 Drained and Effective Shear Strength of Clays 1306.7 Shear Strength of Granular Soils 132References 1367 California Bearing Ratio 1387.1 Correlations with Soil Classification Tests 1397.2 Correlations with Soil Classification Systems 1447.3 CBR and Undrained Shear Strength 1447.4 An Alternative to CBR Testing 148References 1498 Shrinkage and Swelling Characteristics 1518.1 Identification 1518.2 Swelling Potential 1538.2.1 Swelling Potential in Relation to other Properties 1538.2.2 Reliability of Swell Predictions Based on Correlations 1608.3 Swelling Pressure 160References 1629 Frost Susceptibility 1649.1 Ice Segregation 1649.2 Direct Measurement of Frost Susceptibility 1669.3 Indirect Assessment of Frost Susceptibility 1679.3.1 Grading 1679.3.2 Plasticity 1699.3.3 Predictions Based on Segregation Potential 1719.4 Choosing a Suitable Method of Evaluating Frost Susceptibility 173References 17410 Susceptibility to Combustion 175Reference 17611 Soil-Structure Interfaces 17711.1 Lateral Pressures in a Soil Mass 17711.1.1 Earth Pressure at Rest 17811.2 Friction and Adhesion at Interfaces 18011.2.1 Values Relating to Specific Types of Structure 180References 184Appendix A Soil Classification Systems 186A.1 Systems Based on the Casagrande System 187A.1.1 The Unified System 187A.1.2 The ASTM System 189A.1.3 The British Standard System 189A.2 The AASHTO System 194A.3 Comparison of the Unified, AASHTO and BS Systems 198References 199Appendix B Sampling Methods 200B.1 Pits and Borings 201B.1.1 Trial Pits 201B.1.2 Light Cable Percussion Borings 202B.1.3 Rotary Boring 204B.1.4 Window Samplers and Windowless Samplers 204B.2 Sampling and Samplers 206B.2.1 Disturbed Samples 206B.2.2 Open]Drive Samplers 206B.2.3 Piston Samplers 209B.2.4 The Standard Penetration Test 210B.3 Probes 212B.3.1 Dynamic Probes 212B.3.2 Static Probes 213Reference 217Index 218