Strain Calculator Formula
Understand the math behind the strain calculator. Each variable explained with a worked example.
Formulas Used
Engineering Strain
strain = delta_l / original_lStrain Percentage
strain_pct = delta_l / original_l * 100Microstrain
microstrain = delta_l / original_l * 1e6Variables
| Variable | Description | Default |
|---|---|---|
delta_l | Change in Length(mm) | 0.5 |
original_l | Original Length(mm) | 500 |
How It Works
Engineering Strain
Strain measures the deformation of a body relative to its original size.
Formula
epsilon = delta_L / L_0
where delta_L is the change in length and L_0 is the original gauge length. Strain is dimensionless but is often expressed in microstrain (x 10^6) or as a percentage. Tensile strain is positive; compressive strain is negative.
Worked Example
A 500 mm gauge length bar elongates by 0.5 mm under load.
delta_l = 0.5original_l = 500
- 01epsilon = 0.5 / 500 = 0.001 mm/mm
- 02As percentage: 0.001 x 100 = 0.1%
- 03In microstrain: 0.001 x 10^6 = 1000 microstrain
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