axial strain (due to axial & moment stress)10.01.03.143

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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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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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