Strength of Materials (SOM) Syallabus

Pokhara University

Faculty of Science and Technology

Course Code: STR 210

Course Title: Strength of Materials (3-2-1)

Full Marks: 100

Pass Marks: 45

Nature of Course: Theory and Practical

Total Lectures: 45 hours

Level: Bachelor Program: BE

1. Course Description

This course is designed to develop the competency of the students in the material behavior, stress and strain in structural elements due to external loads and temperature changes.

2. General Objectives

The course is designed to provide fundamental concept on the geometrical properties of different figures, material behavior and strength required to design simple structural members.

3. Methods of Instruction

Lecture, tutorials, discussions and assignments

4. Contents in Detail

Specific Objectives	Contents
Identify the concept of statically determinate and indeterminate structure.	Unit 1: Axial Forces, Shear Forces and Bending Moment (6 hrs) 1.1 Introduction to strength of materials 1.2 Determinate and indeterminate structure 1.3 The concept of superposition of internal forces due to various combination of loads 1.4 Define axial force, shear force and bending moments and their relationships. 1.5 Draw axial forces, shear forces and bending moments in diagrams for statically determinate beam and frames.
Deduceptinciple moment of inertia and locate the principle axes of various geometry and their application in civil engineering.	Unit 2: Geometrical Properties of Section (6 hrs) 2.1 Review of center of gravity and Centroid, Radius of gyration and Moment of Inertia of built-up plane figures, Parallel axis Theorem 2.2 Polar Moment of Inertia 2.3 Product Moment of Inertia 2.4 Principle Moment and Principle axes of inertia for built-up plane figures and standard steel sections 2.5 Mohr's Circle for Principle Moment of Inertia
Discuss properties of elastic constant of a materials and its importance in Civil Engineering design. Calculate elongation and stresses developed in structural element due to different forces.	Unit 3: Direct Stresses and Strains (8 hrs) 3.1 Introduction of internal forces, stresses and strains 3.2 Stress strain diagrams for ductile and brittle materials 3.3 Normal stress-strain, shear stress-strain, Hooke's law, Poisson's ratio, modulus of elasticity, modulus of rigidity, volumetric strain, bulk modulus and their relationship. Multi-axial loading and generalized Hooke's Law 3.4 Factor of safety and permissible stresses. 3.5 Saint-Venant's principle and stress concentration 3.5 Elongation of bars: Uniform/varying cross-sections, tapered section(circular and trapezoidal) due to external axial force 3.6 Compound bars subjected to axial force 3.7 Thermal stresses: single bar, compound / composite bars 3.8 Solving technique for axial indeterminate structure by using compatibility equations
Discuss the concept of principle stresses developed in inclined plane due to normal and shear stress	Unit 4: Principal Stresses (5 hrs) 4.1 Introduction 4.3 Stresses on an inclined plane subjected to two mutually perpendicular normal and shear stresses 4.4 Principal stresses and their positions 4.5 Mohr's circle diagram for principle Stresses

Specific Objectives	Contents
Explain the effect of bending stress, horizontal shear stress at any position of x section and also to determine slope and deflection of beam	Unit 5: Theory of Flexure (8 hrs) 5.1 Introduction to flexure 5.2 General case of bending and pure bending, assumptions, elastic curve, radius of curvature, derivation of bending equation. 5.3 Bending stress variation, position of neutral axis, sectional modulus, flexural stiffness 5.4 Analysis of beams of symmetric cross-section 5.4 Analysis of composite beams 5.5 Shear stress variation in rectangular and symmetrical I - and T- sections 5.6 Concept of slope and deflection in beams, differential equations of deflected shapes, determination of maximum slope and deflection for beams subjected to point load and uniformly distributed load: simply supported beam and cantilever beam
State the strength of circular shaft and list the different types of composite shaft	Unit 6: Torsion of Circular Shafts (3 hrs) 6.1 Introduction 6.2 Assumptions and derivation of torsional equation 6.3 Shear stress variation and torsiosnal rigidity 6.4 Power transmitted by shaft 6.5 Shafts in series and parallel
Explain about the application of thin walled vessel in daily uses, able to calculate stresses developed due to pressure	Unit 7: Thin- Walled Pressure Vessels (3 hrs) 7.1 Introduction of thin walled Vessels 7.2 Types of stresses and strains in thin-walled cylindrical and spherical vessels 7.3. Calculation of stresses and strains in thin-walled vessels
Describe the concept of failure mechanism in different types of column and measure its strength	Unit 8: Column Theory (3 hrs) 8.1 Introduction to column and strut 8.2 Classification of column based on slenderness ratio 8.3 Assumption and derivation of Euler's Formula 8.4 Limitation of Euler's Formula 8.5 Intermediate columns; derivation of column-bucklings 8.6 Introduction to slender column
Explain the bending effect in structural member due to axial and bending moments also locate the position of axial load for no tension	Unit 9: Compound Stresses Failure Theories (3 hrs) 9.1 Introduction to different failure theories 9.2. Load acting eccentrically to one and both axes 9.3. Condition for no tension in the section

5. Laboratories

1. Tensile test and stress-stress curve for steel, aluminum, timber and compressive test in concrete
2. Axial and compressive stress determination
3. Center of gravity and Moment of Inertia of simple plane lamina
4. Simple bending test on beams
5. Torsion test on simple shaft
6. Test on column behavior and buckling

6. Tutorials (30 hrs.)

1. Determination of stability, determinacy and indeterminacy of structures
2. Derivation and numerical based problems on axial force, shear force and Bending moment for beams and frames
3. Derivation and numerical based problems on geometrical properties of 2-D and 3-D figures
4. Determination of stresses and strains on regular and irregular structural members due to external forces, self-weight and temperature change
5. Derivation and numerical based problems on principal stresses and strains
6. Derivation and numerical based problems on flexure and deformation of beams
7. Derivation and numerical based problems on circular shafts due to torsion
8. Derivation and numerical based problems on thin walled vessels
9. Derivation and numerical based problems on columns
10. Derivation and numerical based problems on compound stresses and failure theories

7. Evaluation System and Students' Responsibilities

Evaluation System

In addition to the formal exam(s), the internal evaluation of a student may consist of quizzes, assignments, lab reports, projects, class participation, etc.

Internal Evaluation

Component	Weightage
Theory
Attendance & Class Participation	10%
Assignments	20%
Presentations/Quizzes	10%
Internal Assessment	60%
Practical
Attendance & Class Participation	10%
Lab Report/Project Report	20%
Practical Exam/Project Work	40%
Viva	30%

Total Internal Marks: 50

Semester-End Examination: 50

Full Marks: 50 + 50 = 100

Student's Responsibilities

Each student must secure at least 45% marks separately in internal assessment and practical evaluation with 80% attendance in the class in order to appear in the Semester End Examination. Failing to get such score will be given NOT QUALIFIED (NQ) to appear the Semester-End Examinations. Students are advised to attend all the classes, formal exam, test, etc. and complete all the assignments within the specified time period. Students are required to complete all the requirements defined for the completion of the course.

8. Prescribed Books and References

Text Books

• R. K. Rajput. Strength of Materials (Mechanics of Solids), S. Chand, New Delhi

References

1. G.B. Motra. A text book of strength of materials, Heritage Publishers & Distributors Pvt. Ltd
2. Timoshenko and Gere 'Mechanics of Materials'
3. Beer F.P. and E.R. Johnston "Mechanics of Materials and Structures"
4. E. P. Popov. Mechanics of Materials, 2nd Edition, Prentice Hall of India Pvt. Ltd., New Delhi,1989
5. S. S. Yavikatti. Strength of Materials, Vikas Publication, New Delhi
6. G. H. Ryder. Strength of Materials, 3rd Edition, Macmillan, ELBS, 1985
7. R. K Bansal. A text book of strength of materials, Laxmi publication, New Delhi
8. S. P. Timoshenko & D. H. Young. Elements of Strength of Materials, 5th Edition, East West Press Pvt. Ltd., 1987

Useful Links

• Course Resources Blog
• High Grade Scholar
• Fluid Mechanics Resources

Pokhara University - Faculty of Science and Technology

STR 210 - Strength of Materials Course Syllabus