Transcript Presentation Title - University of Florida

EML 2023 – Stress Analysis
Lecture 1 – Stress State
Static Stress Analysis
• The material we will cover in this topic will be studied in
detail in the courses:
– EGM 3520, Mechanics of Materials
– EML 4500, Finite Element Analysis and Design
EML 2023
Department of Mechanical and Aerospace Engineering
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EML 2023
Department of Mechanical and Aerospace Engineering
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EML 2023
Department of Mechanical and Aerospace Engineering
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Stress and Strain
force
stress,
area
strain,

EML 2023
Department of Mechanical and Aerospace Engineering
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Loading conditions
axial loading
torsion
bending
EML 2023
Department of Mechanical and Aerospace Engineering
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Stress state
the stress state at any point can be
described by 6 values: three normal
stresses and three shear stresses
an orientation can be found such that
there are no shear stresses
the normal stresses are called the
principal stresses
EML 2023
Department of Mechanical and Aerospace Engineering
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von Mises stress
• Von Mises defined a single value for the stress state at a
point based on the six stress values
 von mises 
2
2
1
2
  3  2   2   2 

















x
y
x
z
y
z
xy
xz
yz


2
• in terms of the principal stresses
 von mises 
1
2
2
2
1   2   1   3    2   3  


2
EML 2023
Department of Mechanical and Aerospace Engineering
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von Mises stress
• design objective
– at every point, keep the von
Mises stress below the yield
stress of the material
stress,
force
area
strain,

EML 2023
Department of Mechanical and Aerospace Engineering
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