MODULE 2 LOAD AND STRESS ANALYSIS

1. MODULE 2 LOAD AND STRESS ANALYSIS

2. LOAD AND STRESS ANALYSIS Load Equilibrium equations Complex stresses Stress transformation Mohr’s circle Stress-strain relations Stress concentration

3. Mechanics of Materials • A branch of mechanics that studies the relationships between external loads applied to a deformable body and the intensity of internal forces acting within the body.

4. Typical Engineering Structures Applications involving combined loading

5. Types of Loading on Structures

6. Types of Loading on Structures

7. Equilibrium of a Deformable Body A body is said to be in equilibrium when the resultant of all forces and moments acting on the body is zero.

8. Stress Under General Loading Conditions Stress – intensity of a force acting at a material point

9. Simple Stresses

10. T A • P  Shear stress A  Normal stress Complex Stresses • What is the magnitude of stress and strain on specific plane at A? • Does the stress and strain represent critical / maximum values at A? • If not… • what is the maximum & minimum (principal) stresses and maximum shear stresses? • What is the corresponding strain values? • On which planes do these stresses act?

11. Stress Transformation Equations

12. Mohr’s Circle

13. Fracture Planes

14. Engineering stress, P Engineering strain, s = Ao DL L - Lo e = = Lo Lo Engineering Stress and Strain P Lo L P – applied force Ao – original cross-sectional area Lo – original gage length L – instantaneous length P

15. Engineering Stress-strain Curve s Fractured Tensile failure in ductile material is associated with large plastic deformation. Necking So Fractured eTotal = eel + epl Elastic Plastic e

16. Engineering Stress-strain Curve SS316 steel Non-linear /Power-law  = K(p)n Linear  = E  = E

17. Mechanical Properties of Some Materials

18. Stress Concentration

19. Stress Concentration Stress concentration factor

20. Stress Concentration

21. Stress Concentration Factors