Lecture 5-6

Question 1

Series loading hs a common what

Answer 1

force

Question 2

Series loading has a common what

Answer 2

height

Question 3

Composite loading - when calculating the loading, what should we remember?

Answer 3

To subtract the metal that is used throughout to support the material

Question 4

change in L =

Answer 4

α x change in T x L

coefficient of thermal expansion x change in Temp x original length

Question 5

St Venants principle states that

Answer 5

the material, which is taking a load, far away from where the load acts on the object, the material is undistorted

Question 6

Principle of superposition states that

Answer 6

when a member is under multiple loads, the resultant stress or displacement can be determined by:

1. Finding each stress and displacement to each load
2. Then summing them together

Question 7

When a members cross-section changes, we often see

Answer 7

complex stress distributions

Question 8

K =

Answer 8

Stress concentration factor =

σ max / σ avg

Question 9

When we assume an average stress distribution

Answer 9

the forces which are actually not all equal, are all resolved to be equally distrbuted

Question 10

When problems involve a composite, such as a concrete pillar with steel supports, and a force is applied onto it what do we need to consider?

Answer 10

• The change in length of the concrete and steel are going to be the same
• So equal the equations of E=P L / dL A where dL is th common factor