Principles of Geotechnical Engineering was originally published with a 1985 copyright and was intended for use as a text for the introductory course in geotechnical engineering taken by practically all civil engineering students, as well as for use as a reference book for practicing engineers. The book was revised in 1990, 1994, 1998, 2002, and 2006. This Seventh Edition is the twentyfifth anniversary edition of the text.
CONVERSION FACTORS FROM ENGLISH TO SI UNITS Length: Area: Volume: ft ft ft in in in ϭ 0.3048 m ϭ 30.48 cm ϭ 304.8 mm ϭ 0.0254 m ϭ 2.54 cm ϭ 25.4 mm ft2 ft2 ft2 in.2 in.2 in.2 ϭ 929.03 ϫ 10Ϫ4 m2 ϭ 929.03 cm2 ϭ 929.03 ϫ 102 mm2 ϭ 6.452 ϫ 10Ϫ4 m2 ϭ 6.452 cm2 ϭ 645.16 mm2 ft3 ft3 in.3 in.3 ϭ 28.317 ϫ 10Ϫ3 m3 ϭ 28.317 ϫ 103 cm3 ϭ 16.387 ϫ 10Ϫ6 m3 ϭ 16.387 cm3 Section modulus: in in.3 ϭ 0.16387 ϫ 10 mm ϭ 0.16387 ϫ 10Ϫ4 m3 Hydraulic conductivity: ft/min ft/min ft/min ft/sec ft/sec in./min in./sec in./sec ϭ 0.3048 m/min ϭ 30.48 cm/min ϭ 304.8 mm/min ϭ 0.3048 m/sec ϭ 304.8 mm/sec ϭ 0.0254 m/min ϭ 2.54 cm/sec ϭ 25.4 mm/sec Coefficient of consolidation: in.2/sec in.2/sec ft2/sec ϭ 6.452 cm2/sec ϭ 20.346 ϫ 103 m2/yr ϭ 929.03 cm2/sec Force: lb lb lb kip U.S ton lb lb/ft ϭ 4.448 N ϭ 4.448 ϫ 10Ϫ3 kN ϭ 0.4536 kgf ϭ 4.448 kN ϭ 8.896 kN ϭ 0.4536 ϫ 10Ϫ3 metric ton ϭ 14.593 N/m Stress: lb/ft2 lb/ft2 U.S ton/ft2 kip/ft2 lb/in.2 ϭ 47.88 N/m2 ϭ 0.04788 kN/m2 ϭ 95.76 kN/m2 ϭ 47.88 kN/m2 ϭ 6.895 kN/m2 Unit weight: lb/ft3 lb/in.3 ϭ 0.1572 kN/m3 ϭ 271.43 kN/m3 Moment: lb-ft lb-in ϭ 1.3558 N · m ϭ 0.11298 N · m Energy: ft-lb ϭ 1.3558 J Moment of inertia: in.4 in.4 ϭ 0.4162 ϫ 106 mm4 ϭ 0.4162 ϫ 10Ϫ6 m4 CONVERSION FACTORS FROM SI TO ENGLISH UNITS Length: Area: Volume: Force: 1m cm mm 1m cm mm 1m cm2 mm2 m2 cm2 mm2 ϭ 3.281 ft ϭ 3.281 ϫ 10Ϫ2 ft ϭ 3.281 ϫ 10Ϫ3 ft ϭ 39.37 in ϭ 0.3937 in ϭ 0.03937 in ϭ 10.764 ft ϭ 10.764 ϫ 10Ϫ4 ft2 ϭ 10.764 ϫ 10Ϫ6 ft2 ϭ 1550 in.2 ϭ 0.155 in.2 ϭ 0.155 ϫ 10Ϫ2 in.2 N/m2 kN/m2 kN/m2 kN/m2 kN/m2 ϭ 20.885 ϫ 10Ϫ3 lb/ft2 ϭ 20.885 lb/ft2 ϭ 0.01044 U.S ton/ft2 ϭ 20.885 ϫ 10Ϫ3 kip/ft2 ϭ 0.145 lb/in.2 Unit weight: kN/m3 kN/m3 ϭ 6.361 lb/ft3 ϭ 0.003682 lb/in.3 Moment: 1N·m 1N·m ϭ 0.7375 lb-ft ϭ 8.851 lb-in Energy: 1J ϭ 0.7375 ft-lb 1m cm3 m3 cm3 ϭ 35.32 ft ϭ 35.32 ϫ 10Ϫ4 ft3 ϭ 61,023.4 in.3 ϭ 0.061023 in.3 1N kN kgf kN kN metric ton N/m ϭ 0.2248 lb ϭ 224.8 lb ϭ 2.2046 lb ϭ 0.2248 kip ϭ 0.1124 U.S ton ϭ 2204.6 lb ϭ 0.0685 lb/ft Stress: Moment of inertia: mm m4 ϭ 2.402 ϫ 10Ϫ6 in.4 ϭ 2.402 ϫ 106 in.4 Section modulus: mm3 m3 ϭ 6.102 ϫ 10Ϫ5 in.3 ϭ 6.102 ϫ 104 in.3 Hydraulic conductivity: m/min cm/min mm/min m/sec mm/sec m/min cm/sec mm/sec ϭ 3.281 ft/min ϭ 0.03281 ft/min ϭ 0.003281 ft/min ϭ 3.281 ft/sec ϭ 0.03281 ft/sec ϭ 39.37 in./min ϭ 0.3937 in./sec ϭ 0.03937 in./sec Coefficient of consolidation: cm2/sec m2/yr cm2/sec ϭ 0.155 in.2/sec ϭ 4.915 ϫ 10Ϫ5 in.2/sec ϭ 1.0764 ϫ 10Ϫ3 ft2/sec Principles of Geotechnical Engineering Seventh Edition BRAJA M DAS Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States Principles of Geotechnical Engineering, 7th Edition Braja M Das Executive Director, Global Publishing Program: Chris Carson Senior Developmental Editor: Hilda Gowans Editorial Assistant: Nancy Saundercook Associate Marketing Manager: Lauren Betsos Director, Content and Media Production: Barbara Fuller Jacobsen Content Project Manager: Emily Nesheim Production Service: RPK Editorial Services Copyeditor: Shelly 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ISBN-13: 978-0-495-41130-7 Cover Designer: Andrew Adams ISBN-10: 0-495-41130-2 Cover Images: H Turan Durgunog ˘lu, Zetas, Istanbul, Turkey Cengage Learning 200 First Stamford Place, Suite 400 Stamford, CT 06902 USA Permissions Account Manager, Text: Mardell Glinski Shultz Permissions Account Manager, Images: Deanna Ettinger Text and Images Permissions Researcher: Kristiina Paul Senior First Print Buyer: Doug Wilke Cengage Learning is a leading provider of customized learning solutions with office locations around the globe, including Singapore, the United Kingdom, Australia, Mexico, Brazil, and Japan Locate your local office at: international.cengage.com/region Cengage Learning products are represented in Canada by Nelson Education Ltd For your course and learning solutions, visit www.cengage.com/engineering Purchase any of our products at your local college store or at our preferred online store www.ichapters.com Printed in the United States of America 13 12 11 10 09 To our granddaughter Elizabeth Madison This page intentionally left blank Contents Preface xiii Geotechnical Engineering—A Historical Perspective 1.1 Geotechnical Engineering Prior to the 18th Century 1.2 Preclassical Period of Soil Mechanics (1700–1776) 1.3 Classical Soil Mechanics—Phase I (1776–1856) 1.4 Classical Soil Mechanics—Phase II (1856–1910) 1.5 Modern Soil Mechanics (1910–1927) 1.6 Geotechnical Engineering after 1927 1.7 End of an Era 10 References 12 Origin of Soil and Grain Size 15 2.1 Rock Cycle and the Origin of Soil 15 2.2 Soil–Particle Size 24 2.3 Clay Minerals 26 2.4 Specific Gravity (Gs ) 34 2.5 Mechanical Analysis of Soil 35 2.6 Particle–Size Distribution Curve 42 2.7 Particle Shape 46 2.8 Summary 47 Problems 47 References 50 Weight–Volume Relationships 51 3.1 Weight–Volume Relationships 51 3.2 Relationships among Unit Weight, Void Ratio, Moisture Content, and Specific Gravity 54 v vi Contents 3.3 Relationships among Unit Weight, Porosity, and Moisture Content 57 3.4 Various Unit-Weight Relationships 59 3.5 Relative Density 64 3.6 Comments on emax and emin 67 3.7 Summary 68 Problems 69 References 72 Plasticity and Structure of Soil 73 4.1 Introduction 73 4.2 Liquid Limit (LL) 74 4.3 Plastic Limit (PL) 78 4.4 Shrinkage Limit (SL) 81 4.5 Liquidity Index and Consistency Index 83 4.6 Activity 84 4.7 Plasticity Chart 87 4.8 Soil Structure 88 4.9 Summary 93 Problems 93 References 94 Classification of Soil 95 5.1 5.2 5.3 5.4 5.5 Textural Classification 95 Classification by Engineering Behavior 98 AASHTO Classification System 98 Unified Soil Classification System 102 Summary and Comparison between the AASHTO and Unified Systems 104 Problems 112 References 113 Soil Compaction 114 6.1 6.2 6.3 6.4 6.5 6.6 Compaction—General Principles 114 Standard Proctor Test 115 Factors Affecting Compaction 118 Modified Proctor Test 122 Structure of Compacted Clay Soil 127 Effect of Compaction on Cohesive Soil Properties 129 Contents vii 6.7 Field Compaction 132 6.8 Specifications for Field Compaction 136 6.9 Determination of Field Unit Weight of Compaction 140 6.10 Compaction of Organic Soil and Waste Materials 144 6.11 Special Compaction Techniques 147 6.12 Summary and General Comments 155 Problems 155 References 157 Permeability 160 7.1 Bernoulli’s Equation 160 7.2 Darcy’s Law 162 7.3 Hydraulic Conductivity 164 7.4 Laboratory Determination of Hydraulic Conductivity 166 7.5 Relationships for Hydraulic Conductivity—Granular Soil 172 7.6 Relationships for Hydraulic Conductivity—Cohesive Soils 177 7.7 Directional Variation of Permeability 180 7.8 Equivalent Hydraulic Conductivity in Stratified Soil 182 7.9 Permeability Test in the Field by Pumping from Wells 187 7.10 In Situ Hydraulic Conductivity of Compacted Clay Soils 189 7.11 Summary and General Comments 192 Problems 193 References 196 Seepage 198 8.1 Laplace’s Equation of Continuity 198 8.2 Continuity Equation for Solution of Simple Flow Problems 200 8.3 Flow Nets 204 8.4 Seepage Calculation from a Flow Net 205 8.5 Flow Nets in Anisotropic Soils 209 8.6 Mathematical Solution for Seepage 211 8.7 Uplift Pressure Under Hydraulic Structures 213 8.8 Seepage Through an Earth Dam on an Impervious Base 214 8.9 L Casagrande’s Solution for Seepage Through an Earth Dam 217 8.10 Filter Design 219 8.11 Summary 222 Problems 222 References 225 652 Chapter 18: Subsoil Exploration Problems 18.1 Determine the area ratio of a Shelby tube sampler that has outside and inside diameters of 3.5 in and 3.375 in., respectively 18.2 Repeat Problem 18.1 with outside diameter ϭ 114 mm and inside diameter ϭ 111 mm 18.3 The following are the results of a standard penetration test in sand Determine the corrected standard penetration numbers, (N1 )60 , at the various depths given Note that the water table was not observed within a depth of 12 m below the ground surface Assume that the average unit weight of sand is 15.5 kN/m3 Use Eq (18.10) Depth (m) N 60 1.5 4.5 7.5 12 14 13 18.4 Using the values of N60 given in Problem 18.3 and Eq (18.16), estimate the average soil friction angle, fЈ Use pa Ϸ 100 kN/m2 18.5 The following are the results of a standard penetration test in dry sand 18.6 18.7 18.8 18.9 Depth (m) N 60 1.5 4.5 7.5 12 17 21 23 For the sand deposit, assume the mean grain size, D50 , to be 0.26 mm and the unit weight of sand to be 15.5 kN/m3 Estimate the variation of relative density with depth Use Eq (18.14) A boring log in a sandy soil is shown in Figure 18.16 Determine the corrected standard penetration numbers from Eq (18.13) a From the results of Problem 18.3, estimate a design value of (N1 )60 (corrected standard penetration number) for the construction of a shallow foundation b Refer to Eq (16.47) For a 2-m-square column foundation in plan, what allowable load could the column carry? The bottom of the foundation is to be located at a depth of 1.0 m below the ground surface The maximum tolerable settlement is 25 mm For the soil profile described in Problem 18.5, estimate the variation of the cone penetration resistance, qc , with depth Use Eq (18.30) In a layer of saturated clay, a cone penetration was conducted At a depth of 10 m below the ground surface, qc was determined to be 1400 kN/m2 Estimate the undrained shear strength of the clay Given: unit weight of saturated clay ϭ 18 kN/m2 References Depth (ft) 17.5 ft 653 N60 10 15 20 10 25 12 gsat = 118 lb/ft3 30 14 g = 115 lb/ft3 Sand Figure 18.16 18.10 The average cone penetration resistance at a certain depth in a sandy soil is 205 kN/m2 Estimate the modulus of elasticity of the soil at that depth 18.11 During a field exploration program, rock was cored for a length of ft and the length of the rock core recovered was ft Determine the discovery ratio References AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS (1967) Manual of Foundation Investigations, National Press Building, Washington, D.C AMERICAN SOCIETY OF CIVIL ENGINEERS (1972) “Subsurface Investigation for Design and Construction of Foundations of Buildings, Part I,” Journal of the Soil Mechanics and Foundations Division, ASCE, Vol 98, No SM5, 481–490 AMERICAN SOCIETY FOR TESTING AND MATERIALS (1991) Annual Book of ASTM Standards, Vol 04.08 Philadelphia, Pa ANAGNOSTOPOULOS, A., KOUKIS, G., SABATAKAKIS, N., and TSIAMBAOS, G (2003) “Empirical Correlation of Soil Parameters Based on Cone Penetration Tests (CPT) for Greek Soils,” Geotechnical and Geological Engineering, Vol 21, No 4, 377–387 CUBRINOVSKI, M., and ISHIHARA, K (1999) “Empirical Correlation Between SPT N–Value and Relative Density for Sandy Soils,” Soils and Foundations, Vol 39, No 5, 61–92 DEERE, D U (1963) “Technical Description of Rock Cores for Engineering Purposes,” Felsmechanik und Ingenieurgeologie, Vol 1, No 1, 16–22 DJOENAIDI, W J (1985) “A Compendium of Soil Properties and Correlations.” Master’s thesis, University of Sydney, Australia KULHAWY, F H., and MAYNE, P W (1990) Manual on Estimating Soil Properties for Foundation Design, Final Report (EL-6800) submitted to Electric Power Research Institute (EPRI), Palo Alto, Calif LIAO, S., and WHITMAN, R V (1986) “Overburden Correction Factor for SPT in Sand,” Journal of Geotechnical Engineering, ASCE, Vol 112, No 3, 373–377 654 Chapter 18: Subsoil Exploration MENARD, L (1965) “Rules for Calculation of Bearing Capacity and Foundation Settlement Based on Pressuremeter Tests,” Proceedings, 6th International Conference on Soil Mechanics and Foundation Engineering, Montreal, Canada, Vol 2, 295–299 OSTERBERG, J O (1952) “New Piston-Type Sampler,” Engineering News Record, April 24 PECK, R B., HANSON, W E., and Thornburn, T H (1974) Foundation Engineering, 2nd ed., Wiley, New York ROBERTSON, P K., and CAMPANELLA, R G (1983) “Interpretation of Cone Penetration Tests Part I: Sand,” Canadian Geotechnical Journal, Vol 20, No 4, 718–733 SCHMERTMANN, J H (1970) “Static Cone to Compute Static Settlement Over Sand,” Journal of the Soil Mechanics and Foundations Division, ASCE, Vol 96, No SM3, 1011–1043 SCHMERTMANN, J H (1975) “Measurement of in situ Shear Strength,” Proceedings, Specialty Conference on in situ Measurement of Soil Properties, ASCE, Vol 2, 57–138 SEED, H B., TOKIMATSU, K., HARDER, L F., and CHUNG, R M (1985) “Influence of SPT Procedures in Soil Liquefaction Resistance Evaluations,” Journal of Geotechnical Engineering, ASCE, Vol 111, No 12, 1426–1445 SKEMPTON, A W (1986) “Standard Penetration Test Procedures and the Effect in Sands of Overburden Pressure, Relative Density, Particle Size, Aging and Overconsolidation,” Geotechnique, Vol 36, No 3, 425–447 SOWERS, G B., and SOWERS, G F (1970) Introductory Soil Mechanics and Foundations, Macmillan, New York SZECHY, K., and VARGA, L., (1978) Foundation Engineering—Soil Exploration and Spread Foundtion, Akademiai Kiado, Hungary TROFIMENKOV, J G (1974) “General Reports: Eastern Europe,” Proceedings, European Symposium of Penetration Testing, Stockholm, Sweden, Vol 2.1, 24–39 WOLFF, T F (1989) “Pile Capacity Prediction Using Parameter Functions,” in Predicted and Observed Axial Behavior of Piles, Results of a Pile Prediction Symposium, sponsored by Geotechnical Engineering Division, ASCE, Evanston, Ill., June 1989, ASCE Geotechnical Special Publication No 23, 96–106 Answers to Selected Problems Chapter 2.1 2.3 2.5 2.7 2.9 2.11 Cu ϭ 5.13; Cc ϭ 1.48 Cu ϭ 4.33; Cc ϭ 0.73 b D10 ϭ 0.11 mm; D30 ϭ 0.17 mm; D60 ϭ 0.3 mm c 2.73 d 0.88 b D10 ϭ 0.23 mm; D30 ϭ 0.33 mm; D60 ϭ 0.48 mm c 2.09 d 0.99 Gravel ϭ 0%; Sand ϭ 6%; Silt ϭ 52%; Clay ϭ 42% 0.0052 mm Chapter 3.5 3.7 3.9 3.11 3.13 w ϭ 15.6% ␥ ϭ 121 lb/ft3 ␥d ϭ 104.7 lb/ft3 e ϭ 0.59 n ϭ 0.37 S ϭ 70.6% a 16.91 kN/m3 b 2.44 c 0.417 a 101.1 lb/ft3 b 0.648 c 0.39 d 44.5% a 1423.7 kg/m3 b 0.479 c 53.5% d 222 kg/m3 a 20.59 kN/m3 b 1.99% 655 656 Answers to Selected Problems 3.15 3.17 3.19 3.21 3.23 a 117.4 lb/ft3 b 96.6 lb/ft3 c 77.7% a 0.65 b 126.7 lb/ft3 69.75 lb 18.8 kN/m3 a 74.6% b 111.1 lb/ft3 Chapter 4.1 4.3 4.5 a 28.5 b 16.3 a 39.7 b 21 SL ϭ 19.4% SR ϭ 1.85 Chapter 5.1 5.3 Soil Classification A B C D E Clay Sandy clay Loam Sandy clay and sandy clay loam (borderline) Sandy Loam Soil Symbol Group name SP MH CH SC SC GM-GC CH Poorly graded sand Elastic silt with sand Fat clay Clayey sand Clayey sand Silty clayey gravel with sand Fat clay with sand Chapter 6.1 w (%) ␥zav (lb/ft3) 10 12 15 150.9 140.7 134.6 129.0 121.5 Answers to Selected Problems 6.3 w (%) 10 20 6.5 6.7 6.9 6.11 6.13 6.15 d @ S (%) (kg/m3) 80 90 100 2002 1601 2059 1676 2107 1741 e ϭ 0.358 S ϭ 94% 89.9% Pit B d ϭ 1626.4 kg/m3 R ϭ 96.7% 15.94 kN/m3 20.65; Rating: Fair Chapter 7.1 7.3 7.5 7.7 7.9 7.11 7.13 7.15 7.17 0.022 in./sec h ϭ 16.67 in v ϭ 0.0083 in./sec 0.31 cm2 0.207 m3/min 7.18 ϫ 10Ϫ5 m3/sec/m 0.57 ft/min 0.354 cm/sec 1.52 ϫ 10Ϫ6 cm/sec 36.8 Chapter 8.1 8.3 8.5 8.7 8.9 0.009 cm/sec 0.518 m3/m/day 7.2 m3/m/day 2.1 m3/m/day 0.271 m3/m/day Chapter 9.1 lb/ft2 Point u A B C D 560 1280 2280 0 374.4 873.6 560 905.6 1406.4 657 658 Answers to Selected Problems 9.3 kN/m2 Point u A B C D 45 109 199 0 39.24 88.29 45 69.76 110.71 9.5 9.7 9.9 9.11 9.13 kN/m2 Point u A B C D 65 126.95 153.94 0 29.43 44.158 65 97.52 109.79 13.62 ft 0.019 m3/min 4.88 kN/m2 Depth (m) 11.5 87 140.76 205.37 u 0 Ϫ19.13 34.34 Chapter 10 1 ϭ 129.24 kN/m2 3 ϭ 30.76 kN/m2 n ϭ 51.03 kN/m2 n ϭ 39.82 kN/m2 10.3 1 ϭ 161.1 kN/m2 3 ϭ 68.9 kN/m2 n ϭ 138.5 kN/m2 n ϭ 39.7 kN/m2 10.5 1 ϭ 95 kN/m2 3 ϭ 30 kN/m2 n ϭ 94.2 kN/m2 n ϭ 7.1 kN/m2 10.7 20.15 lb/ft2 10.9 15.32 kN/m2 10.11 674 kN/m 10.1 87 106.13 140.76 171.03 Answers to Selected Problems 10.13 24.54 kN/m2 10.15 @ A: 4492.8 lb/ft2 @ B: 4320 lb/ft2 @ C: 384 lb/ft2 10.17 r (ft) ⌬z (lb/ft2) 12 1821 1803 1739 1293 414 10.19 a b c 20 kN/m2 46.72 kN/m2 6.59 kN/m2 Chapter 11 11.1 11.3 11.5 11.7 11.9 11.11 11.13 11.15 11.17 11.19 0.393 in b 3.1 ton/ft2 c 0.53 b 940 lb/ft2 c 0.133 229 mm 0.596 159.6 days a 0.00034 m2/kN b 6.67 ϫ 10Ϫ8 cm/sec a 240.8 days b 7.33 in 66.7 days a 31.25% b 102.6 days c 25.65 days Chapter 12 12.1 a 41.2° b 0.739 kN 12.3 37.5° 12.5 20 lb/in.2 12.7 68.7 lb/in.2 12.9 127.7 kN/m2 12.11 a 20.8° b 55.4° c ' ϭ 338.7 kN/m2 ϭ 128.7 kN/m2 659 660 Answers to Selected Problems 12.13 72 lb/in.2 12.15 ϭ 15.6° Ј ϭ 24.4° 12.17 a 18° b 64.9 kN/m2 12.19 ⌬d(f) ϭ 17.97 lb/in.2 ⌬ud (f) ϭ 7.01 lb/in.2 12.21 Ϫ93.5 kN/m2 12.23 16.24 kN/m2 Chapter 13 13.1 13.3 13.5 13.7 13.9 13.11 13.13 13.15 13.17 13.19 13.21 13.23 13.25 Po ϭ 281.55 kN/m; –z ϭ 2.33 m Po ϭ 205.7 kN/m; –z ϭ m Pa ϭ 3933.6 lb/ft; –z ϭ ft Pa ϭ 37.44 kN/m; –z ϭ 1.33 m Pp ϭ 12,450 lb/ft; –z ϭ 2.67 ft Pp ϭ 645.8 kN/m; –z ϭ 1.67 m Pa ϭ 2340.8 lb/ft; –z ϭ 2.91 ft Pa ϭ 141.1 kN/m; –z ϭ 2.04 m 402.6 kN/m Pp acts at 1.33 m from the bottom of the wall inclined at an angle  ϭ Ϫ6.64° b 5.74 ft c 3225 lb/ft d Pa ϭ 5233 lb/ft; –z ϭ 3.09 ft 10.02 kN/m Part 1: 85.14 kN/m Part 2: 84.80 kN/m 68.3 kN/m Chapter 14 14.1 14.3 14.5 14.7 1533 kN/m 59,063 lb/ft 710.2 kN/m 267.2 kN/m Chapter 15 15.1 15.3 15.5 15.7 15.9 15.11 15.13 1.63 m 0.98 103.1 ft 1.76 9.19 m; toe failure 3.86 m a 27.5 kN/m2 b Mid-point circle c 5.95 m Answers to Selected Problems 15.15 15.17 15.19 15.21 15.23 0.57 1.5 1.75 0.75 1.09 Chapter 16 16.1 16.3 16.5 16.7 16.9 16.11 16.13 7372 lb/ft2 71 kN/m2 138.7 kN/m2 153 kip 4.1 ft 208.8 kip 207.9 kip Chapter 18 18.1 18.3 18.5 7.54% Depth (m) (N1)60 1.5 3.0 4.5 6.0 7.5 16 10 14 14 12 Depth (m) Dr (%) 1.5 3.0 4.5 6.0 7.5 87 87 84 81 76 18.7 211.8 kN/m2 18.9 66.7 kN/m2 18.11 75% 661 Index A AASHTO classification, 98–100 Absolute permeability, 165 Active pressure: braced cut, 503–506 Coulomb, 457–459 Rankine, 432–434 Active thrust, braced cut, 503–506 Activity, 84–87 Adhesion, 376 Adsorbed water, 33 Aeolian soil, 22 A-line, 87 Alluvial soil, 22 Alumina octahedron, 26–27 Angle of friction: consolidated-undrained, 391 definition of, 365 drained, 366 drained, clay, 374 foundation material and soil, 376–378 residual, clay, 374–375 typical values for, 366 Angularity, 47 Anisotropic soil, flow net, 209–210 Anisotropy, clay, 403–405 Anisotropy ratio, 181 A parameter, 392 Area ratio, 639 Atterberg limit, 73 662 Auger, 631–632 Average degree of consolidation, 333–334 B Bearing capacity, shallow foundation: based on settlement, 602–604 depth factor, 592 eccentric load, 597–600 effective area, 598 effective width, 598 effect of ground water table, 584–585 factor of safety, 586–687 factors, general, 590–591 factors, Terzaghi, 582, 584 general equation, 592 gross allowable, 586 inclination factor, 592 net allowable, 586 shape factor, 592 Terzaghi’s equation, 581–582 Blasting, compaction, 154 Boiling, 232 Bottom ash, compaction, 146 Boussinesq’s solution, 260–261 Bowen’s reaction principle, 15–16 B parameter: definition of, 381 typical values for, 382 Braced cut: active thrust, cohesive soil, 504, 506 active thrust, granular soil, 503–505 general, 499–502 Brownian motion, 91 Brucite sheet, 28 C Calding’s equation, 407 Capillary rise, 243–245 Chemical sedimentary rock, 22 Chemical weathering, 19 Chopping bit, 634 Classification, particle size, 24–26 Clay, 26 Clay liner: compaction, 612–616 double, 623–624 single, 622 single, geomembrane, 622 Clay mica, 28 Clay mineral, 26–34 Cluster, structure, 92 Coefficient: active pressure with earthquake, 469 compressibility, 332 consolidation, 332 Coulomb’s active pressure, 458 Index Coulomb’s passive pressure, 467 earth pressure at rest, 427–428 gradation, 42 Rankine active pressure, 432–434 Rankine passive pressure, 434–436 sorting, 43 volume compressibility, 332 Cohesion, definition of, 365 Colluvial soil, 22 Compaction: blasting, 154 bottom ash, 146 compaction effort, 120–122 copper slag, 146 dynamic, 151–153 effect of soil type, 118–120 effect on hydraulic conductivity, 129 general principles, 114–115 modified Proctor test, 122–124 maximum dry unit weight, 115 optimum moisture content, 115 organic soil, 144–145 relative, 136 soil-organic material mixture, 145–146 specifications for, 136–137 standard Proctor test, 115–118 zero-air-void unit weight, 118 Compression index, 319–320 Cone penetration test, 646–648 Consistency, 72 Consolidated-drained triaxial test, 381–385 Consolidated-undrained triaxial test, 389–393 Consolidation: coefficient of, 332 degree of, 333 effect of sample disturbance, 316–317 laboratory test, 308–312 logarithm-of-time method, 339–340 overconsolidation ratio, 315 preconsolidation pressure, 314–315 secondary, 326–328 settlement calculation, 317–319 spring-cylinder model, 305 square-root-of-time method, 340 time rate of, 330–335 void ratio-pressure plot, 310–312 Constant head test, 166–167 Contact pressure, 294–296 Continuity equation, Laplace, 198–200 Continuous plagioclase reaction series, 17 Copper slag, compaction, 146, 147 Coulomb’s earth pressure: active, 457–459 graphical solution, 461, 463–465 passive, 466–468 Criteria filter, 219–222 Critical hydraulic gradient, 232 Cross-plane hydraulic conductivity, 617–618 Culmann’s solution, 461, 463–465 D Darcy’s law, 162 Degree of consolidation, 333 Degree of saturation, 52 Density: definition of, 53 relative, 64–66 Depth of tensile crack, 446 Detrital sedimentary rock, 22 Diffuse double layer, 31 Dipole, 31 Direct shear test, 369–375 Discharge velocity, 162 663 Discontinuous ferromagnesian reaction series, 17 Dispersing agent, 39 Disturbance, effect on consolidation, 316–317 Domain, structure, 92 Double layer water, 33 Drained angle of friction, 366 Drilled shaft foundation, 576 Dry density, 53 Dry unit weight, 53 Dynamic compaction, 151–152 Dynamic earth pressure: c′−φ′ soil, 474–477 E Earth dam, seepage, 214–216 Earth pressure at rest: coefficient of, 427–428 normally consolidated clay, 428 overconsolidated clay, 428 Effective size, 42 Effective stress: definition of, 226 Elastic settlement, 296–303 Elasticity modulus, 302 Elevation head, 160 Empirical relations, hydraulic conductivity, 172–174, 177–179 Equipotential line, 204 Equivalent hydraulic conductivity, 182–184 Evaporite, 23 F Factor of safety, slope: clay embankment, 568–571 cohesion, 515 friction, 515 strength, 514–515 Failure criteria, MohrCoulomb, 365 Falling head test, 167–168 664 Index Field unit weight: nuclear method, 141 rubber balloon method, 141 sand cone method, 140–141 Field vanes, 408–409 Filter: criteria, 219–222 definition of, 219 Finite slope, 519–520 Fissure eruption, 15 Flight auger, 631–632 Flocculation, 91 Flow channel, 205 Flow index, 75 Flow line, 204 Flow net, 204–205 Foundation material, friction angle, 376–378 Friction circle, 537 G Gap-graded soil, 43 Geomembrane, 619–621 Geonet, 621 Geotextile, 616–619 Gibbsite sheet, 27 Glacial soil, 22 Gradation coefficient of, 42 Gravel, 24 Group index, classification, 99 H Hazen’s equation, 172 Hazen’s formula, capillary rise, 243–245 Head: elevation, 160 pressure, 160 velocity, 106 Heaving, factor of safety, 240–241 Honeycombed structure, 90 Hydraulic conductivity: bonding between lifts, effect of, 614 definition of, 162 directional variation of, 180–181 effect of temperature, 165 empirical relations for, 172–175, 177–179 equivalent, 182–184 size of clay clods, 612 typical values, 165 Hydraulic gradient, 161 Hydrogen bonding, 31 Hydrometer analysis, 37–42 I Igneous rock, 15–17 Illite, 28 Immediate settlement, 294–303 Index: compression, 319–320 consistency, 84 liquidity, 83–84 plasticity, 79 swell, 320–321 Influence chart, 285–298 Influence value, stress, 297 Isomorphous substitution, 29 K Kaolinite, 28 Kozeny-Carman equation, 172 L Laboratory test, consolidation, 308–312 Lacustrine soil, 22 Laminar flow, 161 Laplace’s equation of continuity, 198–200 Leachate removal system, 624–626 Line load, stress, 262–265 Liquidity index, 83 Liquid limit: definition, 73 one point method, 77 typical values for, 80 Logarithmic spiral, 490–492 Logarithm-of-time method, consolidation, 339–340 M Magma, 15 Major principal stress, 255 Marine soil, 22 Mat foundation, 576 Maximum dry unit weight, compaction, 115 Mechanical weathering, 19 Metamorphic rock, 23–24 Mid-point circle, 523 Minor principal stress, 255 Modified Proctor test, 122–124 Mohr-Coulomb failure criteria, 365 Mohr’s circle, 255–256 Moist unit weight, 53 Moisture content, 52–53 Mononobe-Okabe solution: active pressure coefficient, 469 equation for, 469 line of action, active force, 473–474 Montmorillonite, 29 N Needle punched nonwoven geotextile, 617 Neutral stress, 228 Nonwoven geotextile, 617 Normally consolidated clay, 314 Normal stress plane, 254 Nuclear method, compaction, 141 O Octahedral sheet, 27 Oedometer, 308 One point method, liquid limit, 77 Optimum moisture content, 115 Ordinary method of slices, slope, 544–547 Organic soil, compaction, 144–145 Overconsolidated clay, 314 Overconsolidation ratio: definition of, 315 variation of Af, 392–393 P Partially saturated soil, effective stress, 245–246 Particle shape, 46–47 Index Particle size distribution curve, 37 Passive pressure: Coulomb, 466–468 curved failure surface, 492–499 Rankine, 434–436 wall friction, 488–490 Peak shear strength, 371 Peat, 110 Peds, 92 Percent finer, 37 Percussion drilling, 634 Permeability test: constant head, 166–167 falling head, 167–168 Permeability test pumping from wells, 187–189 Permittivity, 618 Piezometer, 161 Pile, 576 Piston sampler, 638 Plane, principal, 255 Plasticity chart, 86–88 Plasticity index, 79 Plastic limit, 78 Plate load test, 604–606 Pluton, 15 Pneumatic roller, 132 Pocket penetrometer, 411 Point load, stress, 260–261 Poisson’s ratio, 303 Poorly graded soil, 43 Pore pressure parameter: A, 389, 393 B, 381–382 Pore water pressure: definition of, 228 in zone of capillary rise, 246 Porosity, 52 Potential drop, 206 Preconsolidation pressure: definition of, 314 graphical construction for, 314 Pressure head, 160 Pressuremeter test, 644–645 Primary leachate collection system, 624–625 Principal plane, 255 Principal stress, 255 Q Quartzite, 24 Quick condition, 232 R Rankine active state, 433 Rankine theory: active pressure, 432–434 coefficient of active pressure, 434 coefficient of passive pressure, 435 depth of tensile crack, 446 passive pressure, 434 – 436 Reaction principle, Bowen, 15 Rectangular loaded area, stress, 278–283 Relative compaction, 136 Relative density, 64–66 Residual friction angle, clay, 374, 375 Residual soil, 22 Retaining wall: cantilever, 480 counterfort, 480–481 gravity, 480 mechanically stabilized earth, 481–482 Rock coring, 648–650 Rock cycle, 18 Rock quality designation, 649–650 Roller: pneumatic, 132 sheepsfoot, 134 smooth-wheel, 132 vibratory, 134 Rotary drilling, 634 Rubber balloon method, field unit test, 141 S Sand, 24 Sand cone method, 140–141 Saturation, degree of, 52 Secondary compression index, 326 665 Secondary consolidation, 326–328 Sedimentary rock, 22–23 Seepage: force, 235–236 through earth dam, 214–219 velocity, 163 Sensitivity, 401 Settlement calculation, consolidation, 317–319 Shallow foundation: general shear failure, 578 local shear failure, 579 Shape, particle, 46–47 Shear stress, plane, 254 Sheepsfoot roller, 134 Shelby tube, 638 Shrinkage limit, 81–84 Shrinkage ratio, 82 Sieve analysis, 35–37 Sieve size, 35 Silica tetrahedron, 26–27 Silt, 24 Single-grained structure, 89 Slip plane, 438 Slope stability: base failure, 523 Bishop’s simplified method, 548–550 Culmann’s method, 520–522 friction circle, 537 infinite slope, without seepage, 515–517 infinite slope, with seepage, 518 Michalowski’s solution, 538, 541, 557, 559 ordinary method of slices, 544–547 rapid drawdown, 565–567 slope failure, 512–514 Spencer’s solution, 557–558 stability number, slope, 526 Smooth-wheel roller, 132 Sorting coefficient, 43 Specific gravity: definition, 34 typical values for, 35 666 Index Specific surface, 28 Spiral, logarithmic, 490–492 Spring-cylinder model, consolidation, 304–306 Square-root-of-time method, 340 Standard penetration number, 636–637 Standard Proctor test, 115–118 Standard split spoon, 635 Stoke’s law, 37 Stress: influence chart for, 285–287 line load, 262–265 Mohr’s circle for, 255–256 path, 414–417 point load, 260–261 principal, 255 rectangularly loaded area, 278–283 strip load, 266–267 uniformly loaded circular area, 273–275 Structure, compacted clay, 127–128 Surface tension, 243 Swell index, 320–321 T Tensile crack, 446 Textural classification, 95–96 Thixotropy, definition of, 402 Time factor, 333 Time rate of consolidation, 330–335 Torvane, 411 Total stress, 226 Transmissivity, 618 Triaxial test: consolidated-drained, 381–385 consolidated-undrained, 389–393 general, 380–381 unconsolidated-undrained, 395–397 Turbulent flow, 161 U U-line, 88 Ultimate strength, 371 Unconfined compression strength, 397 Unconfined compression test, 397–398 Unconsolidated-undrained test, 395–397 Undrained shear strength: definition of, 395 empirical relations for, 398–399 Unified classification system, 102–104 Uniformity coefficient, 42 Uniformly loaded circular area, stress, 273–277 Unit weight: definition of, 53 dry, 53 moist, 53 relationship for, 59 Uplift pressure, 213–214 V Vane shear test: correlation for, 409, 411 procedure for, 406–409 Varved soil, 184 Velocity: discharge, 162 head, 160 seepage, 163 Vibratory roller, 134 Vibroflot, 148, 150 Vibroflotation, 148–151 Virgin compression curve, 316 Void ratio, 51 Void ratio-pressure plot, 310-312 Volcanic eruption, 15 Volume compressibility, coefficient of, 332 W Wall friction, passive pressure, 488-490 Wall yielding, earth pressure, 436-438 Wash boring, 634 Weathering, 19-21 Well graded, 43 Woven geotextile, 616 Z Zero-air-void unit weight, 118 ... deals with the study of the physical properties of soil and the behavior of soil masses subjected to various types of forces Soils engineering is the application of the principles of soil mechanics... problems Geotechnical engineering is the subdiscipline of civil engineering that involves natural materials found close to the surface of the earth It includes the application of the principles of. .. various types of geotechnical engineering problems They still remain an important and useful computation tool in our profession Since the early days, the profession of geotechnical engineering