## SF4102 - Strength and Deformation Behaviour of Soils (Syllabus) 2021-regulation Anna University

SF4102

STRENGTH AND DEFORMATION BEHAVIOUR OF SOILS

LTPC

3003

OBJECTIVES:
• To impart knowledge to characterize stress-strain behaviour of soils, the failure criteria and to evaluate the shear strength and compressibility parameters of soils.

UNIT I

SHEAR STRENGTH OF COHESIONLESS SOILS

9

Introduction-Shear strength of soil-cohesion-angle of internal friction-Shear strength of granular soils - Direct shear - Triaxial Testing- Drained and undrained Stress-strain behaviour - Dilation, contraction and critical states - Liquefaction and cyclic mobility of saturated sands. Factors influencing stress – strain characteristics – shear strength.

UNIT II

SHEAR STRENGTH OF COHESIVE SOILS

9

Shear strength of normally consolidated and over consolidated clays - Stress-strain behaviour - Total stress and effective stress approach - Triaxial testing and stress path plotting - pore pressure parameters of Skempton and Henkel - shear strength of partially saturated clay in terms of stress state variables. Factors influencing stress – strain characteristics – shear strength.

UNIT III

FAILURE THEORIES

9

Concepts of yield and failure in soils- Failure theories of Von Mises, Tresca and their extended form, their applicability to soils - Detailed discussion of Mohr - Coulomb failure theory.

UNIT IV

CONSTITUTIVE MODEL AND DEFORMATION MODULUS OF SOILS

9

Constitutive law for soil – linear, non linear model- hyperbolic idealisation – Mohr-Columb model- Hardening law-Hardening soil model- Hardening soil model with small strain stiffness- Soft soil - Soft soil model - limitation of all models- Deformation modulus for different type of loadings – Poisson’s ratio.

UNIT V

CRITICAL STATE SOIL MECHANICS

9

The critical state line- Roscoe’s surface- Hvorslev’s surface- Behavior of sand- Effects of dilation- Limitations of Taylor model- Elastic and plastic deformation-Camclay critical state model- Modified Camclay model- Parameters for design

TOTAL : 45 PERIODS

OUTCOMES: On completion of the course, the student is expected to be able to
CO1 Select the shear strength parameters of cohesionless soil based on mode of shear, drainage conditions and differentiate the cyclic stress – strain behaviour of cohesionless soil due to earthquake loading.
CO2 Select the shear strength parameters of cohesive soil based on mode of shear, drainage conditions, degree of saturation and degree of consolidation
CO3 Apply different failure criteria and its applicability based on drainage conditions and type of soil.
CO4 Apply constitutive models for soils and their applicability for different type of drainage conditions.
CO5 Explain critical state behaviour, modelling of soils and to select the respective design parameters.

REFERENCES:
1. Robert D. Holtz., William D. Kovacs., Thomas C. Sheahan., “An Introduction to Geotechnical Engineering” Dorling Kindersley India pvt. Ltd., Second edition, 2013.
2. Braja, M, Das., "Advanced soil mechanics", CRC Press, fifth edition, 2019.
3. Atkinson J.H. and Brandsby P.L. "Introduction to critical state soil mechanics" McGraw Hill, 1978.
4. Lambe, T.W. and Whitman R.V. "Soil Mechanics in S.I. Units John Wiley, India, Pvt Ltd. 2008.
5. Wood, D.M., "Soil behaviour and Critical State Soil Mechanics", Cambridge University Press, New York, 1990.
6. Graham Barnes, "Soil Mechanics Principles and Practices", Macmillan Press Ltd., London, 2002.
7. Braja, M. Das, "Principles of Geotechnical Engineering", Brooks/Cole, Thomson Learning Academic Resource, Center, Fifth Edition, 2002.
8. Malcolm D. Bolton, "A guide to soil mechanics", Universities Press (India) Private Ltd., Hyderabad, India, 2003.
9. Ian Smith, “Elements of Soil Mechanics”, John Wiley & Sons, UK, 9th edition, 2014.
10. Braja, M. Das, "Fundamentals of Geotechnical Engineering", Brooks/Cole, Thomson Learning Academic Resource, Center, 2000.
11. Muni Budhu, Soil Mechanics and Foundations, John Wiley and Sons, Inc., third edition, 2011.
12. Punmia.B.C., Ashok K.Jain, Arun K.Jain., “Soil Mechanics and Foundations”, Lakshmi Publications, seventeenth edition, 2017.