1. ENGR 220 Section

2. Plane Strain Review of Strain
Deformation due to a stress is specified using the concept of normal and shear strain.

3. Normal Strain
Elongation or contraction of a line segment per unit of length.

4. Shear Strain
The change in angle the occurs between two line segments that were originally perpendicular.

5. Volume and shape deformations

6. Plane Strain

7. Strain Gauges

8. Strain Gauge

9. Strain Gauge

10. Strain Rosette

11. Generic Solution Strain measured along three axes at angles a b c
Transform along x-y coordinates
Stain Transformation Equations.

13. 45˚ Strain Rosette

14. 60˚ Strain Rosette

15. Principal Strains

16. Maximum In-Plane Shear Strain

17. Mohr’s Circle

18. Mohr’s Circle

19. Problem 10-2: Determine the in-plane strains of an element orientated at θ=20° counter-clockwise from the original position.

20. 10.12 (10.3 8e) A strain gauge is mounted on the 1 inch diameter A-36 steel shaft as shown below. When the shaft is rotating with an angular velocity of 1760 rpm, the reading on the strain gauge is 800 (10-6). Determine the power output of the motor. Assume the shaft is subjected only to a torque.