L6: Theories of Failure

Question 1

When does failure occur when a solid object is under uniaxial stress (and how is this displayed on a Mohr Circle)

Answer 1

Question 2

W hat are the three potential failure criteria that can be used when taking multi-axial stresses into consideration

Answer 2

1. Maximum Principal Stress (Rankine)
2. Maximum Shear Stress (Tresca)
3. Maximum Shear Strain Energy (Von Mises)

Question 3

When does Rankine Failure Occur

Answer 3

Question 4

How can a case for σfailure = 100MPa be shown on a principal stress diagram for Plane Stress (where σ3=0) Rankine Failure

Answer 4

Question 5

What is Rankine Failure Criterion mainly used for

Answer 5

Question 6

What is maximum Shear Stress (Tresca) Failure Criterion

Answer 6

Question 7

What does a Mohr Circle showing 3 principal stresses look like

Answer 7

Question 8

How can a case for σyield = 100MPa be shown on a principal stress diagram for Plane Stress (where σ3=0) - Tresca Criterion

Answer 8

Question 9

Answer 9

Question 10

What is the Von Mises Failure Criterion

Answer 10

Question 11

How are W and U found through the Von Mises Faiiure Criterion

Answer 11

Question 12

How can the Strain Energy Density in Shear, U per unit Volume be found in the Von Mises failure Criterion

Answer 12

Question 13

How can the yield stress for the Von Mises Failure Criterion be calculated

Answer 13

Question 14

What criteria must be met to avoid failure in the von Mises Criterion

Answer 14

Question 15

How can a case for σyield = 100MPa be shown on a principal stress diagram for Plane Stress (where σ3=0) - Von Mises Failure Criterion

Answer 15

Question 16

Answer 16

Question 17

What is the graph envelope for Plane Stress (σ3=0) ductile material failure comparison (between Tresca and Von Mises) - Which stress is lower

Answer 17

Question 18

How can σx be found using moment of inertia and moment

Answer 18

Question 19

What would the SFD be for the following

Answer 19

Question 20

Which one will be stiffer and stronger, why?

Answer 20

Question 21

Answer 21

Question 22

Equation to find INAx of a cross beam section in a plane beam

Answer 22

Question 23

Equation to find normal stress along the x axis in a plane Beam

Answer 23

Question 24

Equation to find shear stress along xy axis in a plane beam

Answer 24

Question 25

Solution Strategy for finding the maximum shear stress for a beam under given loading

Answer 25

Question 26

How does bending affect the Mohr Cicle when taking shear stress at different points

Answer 26

Question 27

How can something under shear load be shown on a Mohr Circle

Answer 27

Question 28

Answer 28

Question 29

What are the Stages for solving maximum bending stresses, shear stresses, and finding out a beam under a certain load will fail, i.e for a problem similar to this

Answer 29

Question 30

Where is failure most likely to occur in rectangular beam sections and beams with thin web sections like I-Beams

Answer 30

Question 31

Answer 31