Question

The loss of stress with the time at constant strain is called
1. relaxation
2. creep
3. shrinkage
4. ductility

Answer 1

Correct Answer - Option 1 : relaxation

Concept:

Loss of stress due to relaxation of steel

Relaxation is assumed to mean the loss of stress in steel under nearly constant strain at constant temperature.

It is similar to creep of concrete. Loss due to relaxation varies widely for different steels and the steel manufacturers based on test data may supply its magnitude.

This loss is generally of the order of 2 to 8% of the initial stress. This is generally - 1000 hours of referred to at loading at 27˚ C.