Soil Mechanics and Foundation Engineering has seen unprecedented growth over the last few decades both in terms of knowledge and practice as well as in its significance in civil engineering profession. Over 1300 numerical and objective questions with solutions have been included in the book. Questions from competitive exams such as GATE, IES, IAS, IFS, etc., involve some of the subtle and fine concepts of the subject and their practical application, which cannot be gained by simple reading of the subject. Keeping this in view, about 600 questions from these examinations from a long span of over 25 years (1987 onwards) have been solved in the book.

Contents
1.5 Professional Activities in Geotechnical Engineering



2 Origin and Formation of Soils

2.1 Introduction

2.2 Soil Formation

2.3 Weathering

2.4 Erosion

2.5 Factors Influencing Weathering and Soil Formation

2.6 Residual Soils

2.7 Transported Soils

2.8 Types of Soil Profile

2.9 Soil Horizons

2.10 Soil Deposits of India



3 Soil Mineralogy and Structure

3.1 Introduction

3.2 General Types of Soils Based on Particle Size

3.3 Soil Mineralogy

3.4 Primary and Secondary Minerals

3.5 Bonding in Soils

3.6 Mineralogy of Fine-Grained Soils

3.7 Kaolinite

3.8 Montmorillonite

3.9 Illite

3.10 Chlorite

3.11 Vermiculite

3.12 Isomorphous Substitution

3.13 Properties of Clay Minerals

3.14 Identification of Clay Minerals

3.15 Soil Structure and Soil Fabric

3.16 Mineralogy of Cohesionless Soils



4 Physical Properties of Soils

4.1 Introduction

4.2 Three-Phase System of Soil

4.3 Phase Diagram of Soil

4.4 Physical Properties of Soils

4.5 Functional Relationships between Physical Properties

4.6 Physical Properties in Terms of Mass

4.7 Functional Relationships of Physical Properties in Terms of Mass

4.8 Preparation of Soil Samples for Determination of Physical Properties

4.9 Determination of Water Content

4.10 Determination of Specific Gravity

4.11 Determination of in-situ Density

4.12 Relative Density



5 Plasticity Characteristics of Soils

5.1 Introduction

5.2 Consistency

5.3 Consistency Limits

5.4 Liquid Limit

5.5 Plastic Limit

5.6 Index Properties of Soils

5.7 Shrinkage Limit

5.8 Uses of Consistency Limits

5.9 Classification of Soils Based on Index Properties



6 Soil Classification

6.1 Need for Soil Classification

6.2 Particle Size Classification

6.3 Scientific Basis for Soil Classification

6.4 Grain Size Analysis of Soil

6.5 Grain Size Distribution Curve

6.6 Textural Classification

6.7 AASHTO Classification

6.8 Unified Soil Classification System

6.9 Indian Standard Soil Classification (IS:1498 - 1970)

6.10 Field Identification Tests for Fine-Grained Soils



7 Stresses Due to Self-Weight

7.1 Introduction

7.2 Total Stress

7.3 Pore Water Pressure

7.4 Effective Stress Principle

7.5 Effective Stress



8 Vertical Stress Due to Applied Loads

8.1 Introduction

8.2 Boussinesq Theory for Vertical Stress Due to Concentrated Load

8.3 Vertical Stress below Strip Footing

8.4 Newmark’s Influence Chart

8.5 Westergaard’s Theory for Vertical Stress

8.6 The 2:1 Distribution Method

8.7 Comparison of Different Methods for Determination of Vertical Stress



9 Permeability of Soils

9.1 Introduction

9.2 Types of Soil Water

9.3 Flow of Water through Soil

9.4 Permeability

9.5 Darcy’s Law

9.6 Coefficient of Absolute Permeability

9.7 Factors Affecting Permeability of Soils

9.8 Determination of Permeability

9.9 Constant Head Permeability Test

9.10 Falling Head Permeability Test

9.11 Capillary Permeability Test

9.12 Consolidation Test

9.13 Permeability of Stratified Soil Deposits



10 Seepage Analysis

10.1 Introduction

10.2 Types of Soil Formations

10.3 Basic Definitions

10.4 In Situ Tests for Determination of Permeability

10.5 Pumping-Out Tests

10.6 Pumping-In Tests

10.7 Seepage Velocity

10.8 Total Head, Pressure Head, and Datum Head

10.9 Seepage Pressure and Quicksand

10.10 Laplace Equation for Two-Dimensional Flow

10.11 Flow Net

10.12 Methods of Drawing a Flow Net

10.13 Calculation of Hydraulic Parameters from a Flow Net

10.14 Flow Net for Anisotropic Soils

10.15 Phreatic Line in Earth Dams

10.16 Failure of Hydraulic Structures by Piping

10.17 Seepage Control in Hydraulic Structures: Prevention of Piping Failures

10.18 Design of Graded Filter



11 Consolidation

11.1 Introduction

11.2 Significance of Compressibility and Consolidation

11.3 Mechanism of Consolidation: Terzaghi’s Soil-Spring Analogy

11.4 Parameters for Measurement of Compressibility of Soils

11.5 Determination of Consolidation Settlement

11.6 Terzaghi’s Theory of Consolidation

11.7 Odometer or Consolidation Test

11.8 Pre-Compression and Pre-Consolidation Pressure

11.9 Effect of Stress History on Compression of Clays

11.10 Components of Settlement

11.11 Construction Period Correction: Prediction of Field Consolidation Curve

11.12 Acceleration of Consolidation Using Sand Drains

11.13 Three-Dimensional Consolidation



12 Compaction

12.1 Introduction

12.2 Principle of Compaction

12.3 Effect of Compaction on Engineering Properties of the Soil

12.4 Laboratory Compaction Test

12.5 IS Light Compaction Test

12.6 IS Heavy Compaction Test

12.7 Ideal Compaction Curve-Zero Air Void Line

12.8 Compaction Curve for Sands

12.9 Factors Affecting Compaction

12.10 Field Compaction Procedure



13 Shear Strength

13.1 Introduction

13.2 Principal Stresses and Principal Planes

13.3 Mohr’s Circle of Stresses

13.4 Mohr-Coulomb Failure Theory

13.5 Determination of Shear Strength

13.6 Direct Shear Test

13.7 Triaxial Compression Test

13.8 Unconfined Compression Test

13.9 Vane Shear Test

13.10 Bore Hole Shear Test

13.11 Sensitivity

13.12 Pore Pressure Parameters

13.13 Stress Path



14 Soil Exploration

14.1 Introduction

14.2 Need for Soil Exploration

14.3 Planning and Execution of Soil Exploration

14.4 Methods of Soil Exploration

14.5 Soil Samples

14.6 Soil Samplers

14.7 Location of GWT

14.8 In Situ Tests

14.9 Soil Investigation Report



15 Lateral Earth Pressure

15.1 Introduction

15.2 Lateral Earth Pressure

15.3 Types of Lateral Earth Pressure

15.4 Derivation of Expression for Earth Pressure at Rest

15.5 Rankine’s Theory of Active Earth Pressure for Cohesionless Backfill

15.6 Rankine’s Active Earth Pressure for Cohesive Backfill

15.7 Fully Submerged Cohesive Backfill

15.8 Rankine’s Theory of Passive Earth Pressure for Cohesionless Backfill

15.9 Rankine’s Passive Earth Pressure for Cohesive Backfill

15.10 Rankine’s Earth Pressure for Retaining Wall with Inclined Back

15.11 Coulomb’s Wedge Theory for Earth Pressure

15.12 Poncelet (or Rebhan’s) Construction for Active Earth Pressure

15.13 Poncelet (or Rebhan’s) Construction for Passive Earth Pressure

15.14 Culmann’s Construction for Active Earth Pressure

15.15 Coulomb’s Theory of Active Earth Pressure for Cohesive Backfill

15.16 Trial Wedge Method for Lateral Earth Pressure

15.17 Coulomb’s Theory for Passive Earth Pressure for Cohesionless Backfill

15.18 Passive Earth Pressure by Friction Circle Method



16 Retaining Structures

16.1 Introduction

16.2 Selection of Backfill and Drainage

16.3 Types of Retaining Walls

16.4 Cantilever Sheet Pile in Granular Soil

16.5 Cantilever Sheet Pile in Cohesive Soil

16.6 Anchored Sheet Pile in Cohesionless Soil: Free Earth Support Method

16.7 Anchored Sheet Pile in Cohesive Soil

16.8 Anchored Sheet Pile in Granular Soil: Fixed Earth Support Method

16.9 Rowe’s Moment Reduction for Anchored Wall

16.10 Miscellaneous Types of Retaining Structures



17 Stability of Earth Slopes

17.1 Introduction

17.2 Definition of Factor of Safety

17.3 Types of Slope Failures

17.4 Stability Analysis of Infinite Slopes

17.5 Stability Analysis of Finite Slopes: Culmann’s Method

17.6 Stability Analysis of Finite Slopes Using the Swedish Circle Method

17.7 Stability Analysis of Slopes of Earth Dams

17.8 Bishop’s Simplified Method of Slices

17.9 Friction Circle Method

17.10 Taylor’s Stability Number and Stability Charts

17.11 Improving the Stability of Slopes



18 Bearing Capacity of Shallow Foundations

18.1 Introduction

18.2 Design Criteria of Shallow Foundations

18.3 Basic Terms and Definitions

18.4 Rankine’s Theory of Bearing Capacity

18.5 Prandtl’s Theory of Bearing Capacity

18.6 Terzaghi’s Theory of Bearing Capacity

18.7 Types of Shear Failure of Soil

18.8 Skempton’s Theory of Bearing Capacity

18.9 Meyerhof’s Theory

18.10 Hansen’s Theory of Bearing Capacity

18.11 Vesic’s Theory of Bearing Capacity

18.12 IS Code Method



19 Settlement of Shallow Foundations

19.1 Introduction

19.2 Depth of Foundation

19.3 Types of Shallow Foundations

19.4 Components of Settlement

19.5 Steps Involved in Settlement Computation

19.6 Estimation of Settlements for Cohesionless Soils

19.7 Plate Load Test

19.8 Estimation of Settlement for Cohesive Soils

19.9 Correction to Total Settlement for Depth and Rigidity of Foundation

19.10 Differential Settlements and Distortion

19.11 Allowable Settlements

19.12 Indian Standard (IS:1080) Specifications for Foundations



20 Pile Foundations

20.1 Introduction

20.2 Classification of Pile Foundations

20.3 Construction of Piles

20.4 Load-Transfer Mechanism from Pile to Soil

20.5 Estimation of Load Capacity of Piles: Static Formulae

20.6 Estimation of Load Capacity of Piles: Dynamic Formulae

20.7 Estimation of Load Capacity of Pile from SCPT

20.8 Estimation of Load Capacity from SPT

20.9 Estimation of Load Capacity from Load Test on Piles

20.10 Group Action in Piles

20.11 Settlement of a Pile Group

20.12 Negative Skin Friction

20.13 Under-Ream Pile Foundations



21 Well Foundations

21.1 Introduction

21.2 Caissons

21.3 Shapes of Well Foundations

21.4 Components of Well Foundation

21.5 Depth of a Well Foundation

21.6 Forces Acting on Well Foundations

21.7 Stability Analysis of Well Foundations

21.8 Factor of Safety

21.9 Construction of Well Foundations

21.10 Tilting and Shifting of Wells



In CD

22 Soil Dynamics and Machine Foundations

22.1 Introduction

22.2 Types of Machines

22.3 Types of Machine Foundations

22.4 Methods of Dynamic Analysis

22.5 Procedure for Dynamic Analysis of Machine Foundation

22.6 Dynamic Soil Properties

22.7 Design Criteria of Machine Foundations

22.8 Vibration and Shock Isolation



23 Ground Improvement Techniques

23.1 Introduction

23.2 Objectives of Ground Improvement

23.3 Classification of Ground Improvement Methods

23.4 Mechanical Stabilization

23.5 Sand Compaction Piles

23.6 Blasting

23.7 Dynamic Compaction

23.8 Preloading

23.9 Sand Drains

23.10 Prefabricated Vertical Drains

23.11 Stone Columns

23.12 Reinforced Earth

23.13 Soil Nailing

23.14 Geosynthetics

23.15 Foundation Grouting

23.16 In-Situ Soil Mixing

23.17 Seepage Control and Dewatering Systems

23.18 Freezing

23.19 Heating



24 Foundations in Expansive Soils

24.1 Introduction

24.2 Damage to Structures Built on Expansive Soils

24.3 Factors Affecting Seasonal Moisture Variations

24.4 Active Zone

24.5 Mechanism of Swelling

24.6 Factors Influencing Heave

24.7 Estimation of Heave

24.8 Determination of Swelling Pressure

24.9 Identification and Classification of Expansive Soils

24.10 Foundation Techniques in Expansive Soils

24.11 Pavements on Expansive Soils

24.12 Remedial Options



Summary

Objective Questions

Review Questions

Answers

Bibliography

List of IS Codes