Types of Strain Gauges

There are many methods for measuring strain, most of which are based on displacement measurements. The electrical-type strain gauges provide local one- or two-dimensional strain information, while the optical methods can provide whole-field information.

The rest of this section will discuss resistance strain gauges.

Strain measurement devices should:

1. have good spatial resolution, ideally measuring strain at a point
2. be insensitive to changes in ambient temperature; and
3. have high frequency response for dynamic strain measurements.

Resistance strain gauges, the type you will use in this experiment, measure the small displacement that occurs on an object experiencing a mechanical load, and produces a resistance that is proportional to the displacement. These gauges meet all of the above criteria, plus are inexpensive. Hence, they are the most commonly used type of strain gauge.