Strength of Materials

CE25C11

Strength of Materials

Course Objective:

To understand the behaviour of materials under different loading conditions and analyze stresses, strains, bending, torsion, deflection, columns, and pressure vessels.

Stress, Strain and Deformation of Solids: Rigid bodies and deformable solids, Tension, Compression and Shear Stresses, Deformation of simple and compound bars, Thermal stresses, Elastic constants, Volumetric strains, Stresses on inclined planes, Principal stresses and principal planes, Mohr’s circle of stress.

Activity: Assignments and Quiz problems on stress, strain and deformation of solids.

Practical

1. Tensile test on mild steel rod.

2. Hardness test on metals (Rockwell and Brinell Hardness Tests)

Transverse Loading on Beams and Stresses In Beam: Beams, Types, Transverse loading on beams, Shear force and Bending moment in beams, Cantilever, Simply-supported and over-hanging beams. Theory of simple bending Bending stress distribution, Load carrying capacity, Proportioning of sections, Flitched beams, Shear stress distribution.

Activity: Demonstration of practical applications of transverse loading on beams, Simulation of Shear Force and Bending Moment Diagrams using web-based analysis tools.

Practical

1. Double shear tests on metal rod

2. Impact test on metal specimen (Izod and Charpy)

Torsion: Theory of Torsion, Stresses and Deformations in Solid and Hollow Circular Shafts, Combined bending moment and torsion of shafts, Power transmitted to shaft, Shaft in series and parallel, Closed and Open Coiled helical springs – springs in series and parallel.

Activity: Assignments on torsion of solid and hollow circular shafts.

Practical: Torsion test on mild steel rod.

Deflection of Beams and Springs: Elastic curve, Governing differential equation, Double integration method, Macaulay's method, Area moment method, Conjugate beam method for computation of slope and deflection of determinant beams, Strain energy method for determinate beams, Maxwell’s reciprocal theorem, Leaf springs.

Practical

1. Deflection test on metal beam. Verification of Maxwell’s reciprocal theorem.

2. Deflection test on carriage spring.

Columns and Struts: Introduction, Classification of columns, Axially loaded compression members, Euler’s crippling load theory, Derivation of Euler’s critical load formulae for various end conditions, Equivalent length, Slenderness ratio, Euler’s critical stress, Limitations of Euler’s theory, Rankine, Gordon formula, Eccentric loading and Secant formula, Prof. Perry’s formula.

Activity: Model making of light weight bridge.

Practical: Compression test on wood and brick.

Thin Cylinders, Spheres and Thick Cylinders: Stresses in thin cylindrical shell due to internal pressure, circumferential and longitudinal stresses, Deformation in thin cylinders, Spherical shells subjected to internal pressure, Deformation in spherical shells, Thick cylinders, Lame’s theory.

Activity: Assignments and Quiz problems on Thin Cylinders, Sphere and Thick Cylinders.

Tasks:

T1. Design a crane beam used in construction to safely carry heavy loads, considering bending stress and shear force.

T2. Design a transmission shaft for an automobile to transmit required power without failure under torsion and combined loading.

T3. Design a vehicle suspension spring (helical spring) to absorb shocks and provide required comfort based on load and deflection criteria.

T4. Design a building column (steel or concrete) to safely support axial loads, considering buckling and stability conditions.

Weightage: Continuous Assessment: 50%, End Semester Examinations: 50%

Assessment Methodology:

Written Test (40%), Practical (30%), Activity (30%).

Practical: Lab Experiments (50%), Tasks (50%) (Each student must complete a minimum of two tasks).

Activity: Review of GATE/ESE Questions (10%), Mini Project/ Quiz/ Assignment Programs/ Flipped Class /Seminar Presentation (20%)

References:

1. R. K. Bansal, A Textbook of Strength of Materials, 7th Edition, Laxmi Publications, New Delhi, 2024.

2. R. K. Rajput, Strength of Materials: Mechanics of Solids, Revised Edition, S. Chand Publishing, New Delhi, 2022.

3. S. Ramamrutham and R. Narayanan, Strength of Materials, Revised Enlarged Edition, Dhanpat Rai Publishing Company, New Delhi, 2025.

4. R. Subramanian, Strength of Materials, 3rd Edition, Oxford University Press, New Delhi, 2017.

5. S. S. Rattan, Strength of Materials, 4th Edition, McGraw Hill Education, New Delhi, 2021.

6. B. S. Basavarajaiah and P. Mahadevappa, Strength of Materials in SI Units, 3rd Edition, Universities Press, New Delhi, 2010.

7. S. P. Timoshenko and D. H. Young, Elements of Strength of Materials, 5th Edition, East-West Press, New Delhi, 2017.

E-resources:

1. https://onlinecourses.nptel.ac.in/noc25_ce25/preview

2. https://nptel.ac.in/courses/112107147

3. https://archive.nptel.ac.in/courses/105/105/105105108/

4. https://ocw.mit.edu/courses/3-11-mechanics-of-materials-fall-1999/

5. https://ocw.mit.edu/courses/3-11-mechanics-of-materials-fall-1999/pages/lecture-notes/

6. https://www.vlab.co.in/ba-nptel-labs-mechanical-engineering

7. https://solidmechanics.org/

8. https://www.engineeringtoolbox.com/stress-strain-d_950.html

9. https://www.engineeringtoolbox.com/beam-stress-deflection-d_1312.html