1. Lab #5 Due Today Individual Data Processing and Individual Write Up
Lab #5 Report is due TODAY by midnight
Answer Multiple Choice Questions ONLINE TODAY by midnight
Answer Student Survey ONLINE TODAY by midnight
Submit the Lab Report #5 in the drawer labeled “MECE – 204: Strength Lab” beneath the M. E. Mail Folders

2. Lab #5 Report due Today Cover Page + Abstract Data Sheet Spreadsheet
Plot #1: h versus W
Plot #2: Gradient vs. a2
Material Property Tables (two tables)
Comments and Conclusions

3. Combined Loading Test Review Poisson’s Ratio, Bending, Torsion
Superposition Principle in Combined Loading
Strain Rosette and Equations
Strains from Stresses
Principal Stresses and Maximum In-plane Shear Stress

4. Review Poisson’s Ratio

5. Poisson’s Contraction

6. Review Bending Consider the top surface: Longitudinal Contraction
Therefore, Transverse Expansion

7. Bending Stress and Strains
z = -x

8. Deformation in Torsion
Two torques are applied
Circles remain circles
Longitudinal lines become twisted
All angles are equal
End x-section remains flat

9. Shear Strain in Torsion
FG05_01-02UN.TIF
Notes:
Notice the deformation of the rectangular element when this rubber bar is subjected to a torque.
After
Before 9

10. Shear Stress & Torque

11. Combined Loading

12. Both Bending & Torsion

13. Stresses and Strains Bending Torsion Round x-section x = FLbendc/I
xz = FLarmc/J
c = D/2
x = x /E
xz = xz /G
I = D4/64
z = - x
G = E/(2+2)
J = 2 I

14. Stress State under Strain Gage

15. 45 Strain Rosette & Strain Transformations
In our case:
Gage B is aligned along x (axial direction)
Substitute  = -45, 0, +45 for A, B, C gages
And solve for the three strains:

16. Mohr’s Circle & Stress Transformations

17. Conduct the Combined Loading Test
Please initialize the Strain Meter a couple of times to ensure that it indicates zero strains at zero load, and that there is NO DRIFT with time

18. Bending Only (Equations)
M = F * Lbend
x = FLbendc/I
c = D/2
I = D4/64

19. Bending Only (Spreadsheet)

20. Elastic Modulus

21. Poisson’s Ratio

22. Properties (Bending Only)

23. Combined Loading (Stress Analysis)
x = F * Lbend * c/I
z = 0
xz = F * Larm * c/J

24. Stress Analysis (Spreadsheet)

25. Strain Analysis (Equations)
x = x / E
z = -  * x
xz = xz / G

26. Strain Analysis (Spreadsheet)

27. Longitudinal Strain (Plot)

28. Transverse Strain (Plot)

29. Shear Strain (Plot)

30. Lab #5 Due Today Individual Data Processing and Individual Write Up
Lab #5 Report is due TODAY by midnight
Answer Multiple Choice Questions ONLINE TODAY by midnight
Answer Student Survey ONLINE TODAY by midnight
Submit the Lab Report #5 in the drawer labeled “MECE – 204: Strength Lab” beneath the M. E. Mail Folders