Lecture 14 - Stress Determination

Question 1

Give a summary of the quantities measured and the stress relationships for stress determination techniques

Answer 1

Question 2

What are some general ways in which stress is determined?

Answer 2

1 - From strain data - e.g. strain gauges, morie, ESPI, DIC

2 - From combined stress data - e.g. photoelasticity & thermoelasticity, hybrid numerifcal techniques, shear difference method, oblique incidence method

3 - Combined experimental techniques (Data fusion)

N.B. we want to determine stress so that we can compare this directly from stress data on FE

Question 3

When using strain gauge rosettes, how can strain transformations be performed using equations?

Answer 3

Question 4

When using strain gauge rosettes, how can strain transformations be performed using mohrs circle of strain?

Answer 4

Question 5

What is meant by “when the complete strain state is obtained”

Answer 5

The following data is known

Question 6

When the complete strain state is obtained how can Hookes Law be used?

Answer 6

Question 7

Use Mohrs Circle to give a complete definition of stress

Answer 7

Question 8

Some stress determination techniques only give us the sum or the difference in principal stress, how can hybrid numerical methods help us to separate these stresses?

Answer 8