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WELCOME
Dept. of Civil Engineering
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AHSANULLAH UNIVERSITY OF SCIENCE & TECHNOLOGY
Presentated ByShaikh Mahfuzur Rahman
Course No: CE 416Course Teacher:
Munshi Galib Muktadir & Sabreena Nasrin(Lecturer)
4th Year 2nd SemesterSection: CStudent ID: 10.01.03.143
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AXIAL STRAIN
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Key Topics Covered In This Presentation
Strain-Longitudinal StrainTransverse Strain
Stress-Axial StressMoment Stress
Stress Strain Relationship Axial Strain due to Axial Stress & Moment
Stress Consideration of Strain in structural design.
Stress
Internal resistance of force per unit area offered by a body against deformation.
P = External force or loadA = Cross-sectional area
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Axial Stress
A tension or compression stress created in a structural member by the application of a lengthwise axial load.*
7*Definition Copyright ©1989 CRC Press LLC
Example of Axially Loaded Structural Member
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Example of Axially Loaded Structural Member (Truss)
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Strain
Change in dimension of an object under application of external force is strain.Δ L = Change in lengthL o = Initial Length
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o
Strain
Strain is positive in tension (>0) and
negative in compression (<0) Strain is a non-dimensional length Always a fractional value.
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Type of Strain
Longitudinal Strain Transverse Strain
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POISSON'S RATIO:
MOMENT
Moment is the tendency of a body to rotate about an axis as a result of a force acting over a lever arm.
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MOMENT STRESS
Stress that occurs due to moment in a structural member.
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MOMENT STRESS
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Axial Strain & Stress(Axial & Moment Stress) Relationship
The stress imposed on a solid body is directly proportional to the strain produced, within the elastic limit.
i.e. ∝ [Hooke's Law]
=EE=Young’s Modulus
of Elasticity
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• Initial straight line portion
• Max. stress at about 0.002 strain
• Rupture at about 0.003 strain
Behavior of Concrete Under Strain
Stress Strain Behavior of Steel
Compression Controlled Section
Fig. 3c
Strain levels At Different Stress Level
Strain Level At Balanced Condition
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THANK YOU
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Any Question?
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