1. Introduction
to
Strength of Materials
Lecturer;
Dr. Dawood S. Atrushi
atrushiuni@yahoo.com

2. Content of the course
¢ Simple Stress and Strain
¢ Shear Force and Bending Moment
Diagrams in Statically Determinate
Beams
¢ Stresses in Beams
¢ Torsion
Thursday, 2 Strenght of Materials I - DAT October 23, 14

3. Engineering
Mechanics
Statics
Dynamics
Mechanics
of Materials
Thursday, 3 Strenght of Materials I - DAT October 23, 14

4. Study of EXTERNAL
effects on Rigid
bodies
Study of INTERNAL
effects and
Deformations that are
caused by the Applied
loads
Thursday, 4 Strenght of Materials I - DAT October 23, 14

5. Mechanics
of
Deformable
Bodies
Strength
of
Materials
Mechanic
of
Materials
Mechanics
of Solids
Thursday, 5 Strenght of Materials I - DAT October 23, 14

6. ¢ All branches of Engineering deal
with physical systems, the
component parts of which are to
be assigend definite physical
sizes, fabricated from some
materials!
Thursday, 6 Strenght of Materials I - DAT October 23, 14

7. ¢ Appropriate sizing is necessary
for these parts of safety withstand
the imposed forces on them and
at an optimal cost.
¢ DESIGN!
Thursday, 7 Strenght of Materials I - DAT October 23, 14

8. ¢ It is essential to study the
behavior of material from the
strength and deformation
point of view, as well as the
characterization of different
kinds of forces, which cause
different types of stresses in
the material. Thursday, 8 Strenght of Materials I - DAT October 23, 14

9. ¢ The subject, which deals with
the analytical deformation of
the strength, deformation
characteristics (stiffness) and
stability of different members,
is normally designated as the
Strength of Materials.
Thursday, 9 Strenght of Materials I - DAT October 23, 14

10. Characteristics of Strength
of Materials
Strength
Stiffness
Stability
Thursday, 10 Strenght of Materials I - DAT October 23, 14

11. Historical Aspects
¢ Galileo, Leonardo-Da-Vinci, Eraly part
of 17th Centry.
¢ Leonard Euler (1707-1783)
developed theory of columns.
¢ French investigators like, to name a
few Cauchy, Nervier, Poisson,
Coulomb, St. Venant and several
others.
Thursday, 11 Strenght of Materials I - DAT October 23, 14

12. Specific Objectives
It is expected that one should be in a
position to understand
¢ The classification of different kinds of
forces that structural components are
subjected to.
¢ Effects of different forces on such
components and their solution
techniques.
¢ Different types of stresses and
deformations that develop due to forces
Thursday, 12 Strenght of Materials I - DAT October 23, 14

13. Scope
The scope of this particular course
includes;
¢ Identification of different types of
forces that the structural components
will be subjected to.
¢ Systematic evaluation of the effects of
these forces on such structural
components.
Thursday, 13 Strenght of Materials I - DAT October 23, 14

14. Approach
¢ Mainly confined to material useful to
engineering applications.
¢ Laws of Newtonian mechanics that
govern that govern equilibrium of
forces.
¢ Essential to know the mechanical
characteristics of the materials with
which the member will be fabricated.
Thursday, 14 Strenght of Materials I - DAT October 23, 14

15. Units
SI units will be used in this
particular course.
l Meter (m) for length
l Kilogram (kg) for mass
l Second (s) for time
Thursday, 15 Strenght of Materials I - DAT October 23, 14

16. Derived Units
How to derive the units of the
following:
l Area ?
l Velocity ?
l Acceleration ?
l Force ?
Thursday, 16 Strenght of Materials I - DAT October 23, 14

17. Body forces
The body forces act throughout
the body and associated with the
units of volume of the body,
l Gravitational force
l Inertia force
l Magnetic force
Thursday, 17 Strenght of Materials I - DAT October 23, 14

18. Surface Forces
¢ The surface forces act on the surfaces
or area elements of a body
Thursday, 18 Strenght of Materials I - DAT October 23, 14

19. Internal Forces
Thursday, 19 Strenght of Materials I - DAT October 23, 14

20. Internal forces
¢ Free body diagrams
Thursday, 20 Strenght of Materials I - DAT October 23, 14

21. Concept of Stress
¢ Direction of Stresses
¢ Shear Stresses
¢ Normal Stresses
l Tensile
l Compression
Thursday, 21 Strenght of Materials I - DAT October 23, 14

22. ¢ Stresses multiplied by the
respective areas on which they act
give us the forces and at section
the vector sum of these forces is
known as the stress resultant keep
a body in equilibrium.
Thursday, 22 Strenght of Materials I - DAT October 23, 14

23. Example 1
Draw Free-Body Diagram
Thursday, 23 Strenght of Materials I - DAT October 23, 14

24. Example 2
Draw Free-Body Diagram
Review of Static
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Thursday, 24 Strenght of Materials I - DAT October 23, 14

26. Summery
The lessen include:
l A general idea about the scope
of the subject
l Typical application areas
l Concept of different forces
l Concept of free-body diagram
l Concept of Stress
Thursday, 25 Strenght of Materials I - DAT October 23, 14

27. Thank You
Thursday, 26 Strenght of Materials I - DAT October 23, 14