L1: Linear Elasticity

Question 1

Definition of Yield Stress using stress-strain graph of mild steel

Answer 1

Question 2

Definition of Proof Stress using stress-strain graph of Aluminium

Answer 2

Question 3

What is the Shear Modulus or Modulus of Rigidity, G

Answer 3

Question 4

What is Poisson’s Ratio

Answer 4

Question 5

How can the Linear Elastic characteristics of a material be found (and what 4 constants are found)

Answer 5

This results in definition of 4 constants ( E, G σyield and v)
* Elastic Modulus (E =σ/ε) or shear modulus
* G = τ/γ - given by the slope of the initial linear part of the stress-strain plot
* Limit of linearity and elasticity
* σyield = yield stress or σPr = proof stress
* Poisson’s Ratio, v = -transverse strain/longitudinal strain

Question 7

What happens in a Multi-Axial Stress and Strain Relationship (+ Terminology)

Answer 7

Question 8

How does Static Equilibrium work with Complementary Shear Stresses

Answer 8

Question 9

How may Stresses be represented visually in a Multi-Axial Stress and Strain Relationship

Answer 9

Question 10

How do normal stresses act on each face of a cube

Answer 10

Question 11

How do shear Stresses act on each face of a cube

Answer 11

Question 12

Diagram of 3D State of Stress for a Multi-axial stress and strain relationship

Answer 12

3 pairs of normal and 3 pairs of shear stresses acting on the 6 faces.