introduction to strength of materials
TRANSCRIPT
Content of the course
¢ Simple Stress and Strain ¢ Shear Force and Bending Moment
Diagrams in Statically Determinate Beams
¢ Stresses in Beams ¢ Torsion
Thursday, October 23, 14 2 Strenght of Materials I - DAT
Thursday, October 23, 14 Strenght of Materials I - DAT 3
Engineering Mechanics
Statics
Dynamics
Mechanics of Materials
Thursday, October 23, 14 4 Strenght of Materials I - DAT
Study of EXTERNAL effects on Rigid bodies
Study of INTERNAL effects and Deformations that are caused by the Applied loads
Thursday, October 23, 14 5 Strenght of Materials I - DAT
Strength of
Materials
Mechanics of
Deformable Bodies
Mechanics of Solids
Mechanic of
Materials
¢ 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, October 23, 14 6 Strenght of Materials I - DAT
¢ Appropriate sizing is necessary for these parts of safety withstand the imposed forces on them and at an optimal cost.
¢ DESIGN! Thursday, October 23, 14 7 Strenght of Materials I - DAT
¢ 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.
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¢ 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, October 23, 14 Strenght of Materials I - DAT 9
Characteristics of Strength of Materials
Strength
Stiffness
Stability Thursday, October 23, 14 Strenght of Materials I - DAT 10
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, October 23, 14 Strenght of Materials I - DAT 11
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, October 23, 14 Strenght of Materials I - DAT 12
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, October 23, 14 Strenght of Materials I - DAT 13
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, October 23, 14 Strenght of Materials I - DAT 14
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
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Derived Units
How to derive the units of the following:
l Area ? l Velocity ? l Acceleration ? l Force ?
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Body forces
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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
Surface Forces
¢ The surface forces act on the surfaces or area elements of a body
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Internal Forces
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Internal forces ¢ Free body diagrams
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Concept of Stress
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¢ Direction of Stresses
¢ Shear Stresses ¢ Normal Stresses
l Tensile l Compression
¢ 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.
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Example 1
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Draw Free-Body Diagram
Example 2 Draw Free-Body Diagram
Thursday, October 23, 14 Strenght of Materials I - DAT 24
The Civil and Planning Engineering Education DepartmentFaculty of Engineering – State University of Yogyakarta
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The Civil and Planning Engineering Education DepartmentFaculty of Engineering – State University of Yogyakarta
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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, October 23, 14 Strenght of Materials I - DAT 25
Thursday, October 23, 14 Strenght of Materials I - DAT 26
Thank You