CE381
STRUCTURAL ANALYSIS I
AIMS AND OBJECTIVES
This course introduces engineering students to the basic techniques required for
analyzing the majority of structures and the elements of which most structures are
composed, including beams, frames, arches, trusses and cables. It provide methods
also, to compute the deflections of structures.
COURSE CONTENT
Introduction and fundamental concepts in structural analysis. Analysis of trusses,
beams, frames, cables and arches. Stability and determinacy of structures. Analytical
expressions and diagrams. Principles of virtual work. Principle of
virtual
displacements. The unit dummy displacement method. Energy Principles. Potential
energy and strain energy in structural systems. Calculations for deflection of structures.
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TEXT BOOK/ RECOMMENDED READING
Textbook : Structural Analysis, Hibbeler, R. C., Prentice Hall, New Jersey, 2009.
Recommended :
1. Fundamentals of Structural Analysis, Harry H. West, John Wiley&Sons, Inc., Latest
edition.
2. Fundamentals of Structural Analysis, K.Leet, C.-M. Uang , , McGraw Hill, Latest
edition.
ATTENDANCE AND DEADLINES
Attendance will be taken at the at random times, and these will be evaluated in awarding
your grades. Students are responsible for daily assignments. Homework will be due at the
beginning of the lecture on the due date, which will be shown on all homework
assignments. NO LATE ASSIGNMENTS WILL
BE ACCEPTED !!! Missing
assignments will be given a grade of zero. Do not colloborate in solving assignments. You
may see your submission returned with no grade assigned to it. No make-up for quizzes.
Information regarding the course can be found at the web site
http://staff.neu.edu.tr/~rresatoglu
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COMMENTS
Students are strongly recommended to attend and avoid make-up examinations. The students
without official excuse will not be allowed to take make-up examination. You are responsible
for all material handed out in class and all information given in class. Please be prepared for
class and exam : paper, pencil, eraser, ruler, calculator, etc.
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INTRODUCTION
Mechanics, is the branch of physics concerned with the behaviour of physical bodies when
subjected to forces or displacements, and the subsequent effect of the bodies on their
environment.
•
Statics - bodies at rest or moving with uniform velocity
•
Dynamics - bodies accelerating
•
Strength of materials - deformation of bodies under forces.
•
Structural Mechanics - focus on behavior of structures under loads.
Structural Analysis is a process by which the structural engineer determines the response
of a structure to be specified loads or actions.
Response :

Magnitude of force development (collapse)

Magnitude of deformation (serviceability)
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Structural engineering projects can be divided into 4 stages.
1.
•
•
•
2.
3.
4.
Planning phase
Material
Structural form
Loads
Analysis
Design
Construction
The design of a structure involves many considerations, among which are 4 major
objectives that must be satisfied.
1)
2)
3)
4)
Safety (the structure must carry loads safely)
Economy (the stucture should be economical in material and overall costs)
Utility (the structure must meet the performance requirement)
Beauty (the stucture should have a good performance)
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Therefore, the purpose of structural analysis is to determine the reactions, internal forces
and deformations at any point of a given structure caused by applied loads and forces.
Types of Structural forms
• Tension and Compression structures
• Flexural beam and frame structures (load carrying is achieved by bending)
• Surface structures (load carrying is by membrane action)
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1 kN
1 kN
Tension
Compression
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Tensile Failure
Compressive Failure
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Important Structural Properties
Strength : Ability to withstand a given stress without failure. Depends on type of material
and type of force (tension or compression).
Stiffness : Property related to deformation. Stiffer structural elements deform less under
the same applied load. Stiffness depends on type of material (E), structural shape, and
structural configuration.Two main types; Axial stiffness and Bending stiffness.
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Stiff
Stiffer
Stiffest
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Arch
Arches carry the dominant permanent load case
(usually full dead load) in pure axial
compression.
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Truss
C
C
T
C
T
Forces in Truss Members
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1 kN
Bending
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Frame
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Flat Plate
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Folded Plate
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Shells
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Support Connections
• Roller support (allows rotation/translation)
• Pin connection (allows rotation)
• Fixed joint (allows no rotation/translation)
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A beam have a variety of supports.
- roller
( 1-DOF)
- pinned
( 2-DOF)
- fixed
( 3-DOF)
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The process of defining an ideal structure from a real structure is called modeling. To carry
out practical analysis it becomes necessary to idealize a structure.
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A beam have a variety of loads.
- point loads
- distributed loads
- applied moments
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A beam can be classified as statically determinate
beam, which means that it can be solved using
equilibrium equations, or it is ...
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A beam can be classified as statically indeterminate
beam, which can not be solved with equilibrium
equations. It requires a compatibility condition.
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