1. Chapter 8 – Combined Loading
CL = 2 or more stresses at a given point.
Figure: 08-00CO

2. 8.1 Thin-Walled (r/t > 10) Pressure Vessels:
Circumferential or Hoop Stress:
s1 uniform throughout wall!
Figure: 08-01a
Assumption: Thin walled so assume stress uniform throughout the wall!
Normal stress in the hoop direction

3. Longitudinal Stress: Note, this stress = hoop stress/2
Figure: 08-01a
Assumption: Thin walled so assume stress uniform throughout the wall!
Normal stress in the longitudinal direction
Note, this stress = hoop stress/2

4. Summary: Cylindrical Pressure Vessels:
Circumferential or Hoop Stress
Longitudinal Stress
Figure: 08-01c

5. What about Spherical Pressure Vessels?
Figure: 08-01b

6. Examples:
Figure: UNEx8.1

7. Examples:
Figure: P8.5

10. Elastomer volume = 13.8 in3
(was 16.2 in3)
Wall thickness = .10”
RJM 6/2/04