Strain Energy Calculator
Elastic energy stored in a loaded bar — and what it means when it lets go.
A tensioned rock-bolt or crane rope is a loaded spring — this number is the bang when it snaps. Long slender bolts absorb shock better than short fat ones: same stress, more joules.
Formula
Strain Energy Calculator is a free strain energy for design engineers, metallurgists and QA inspectors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Strain Energy Calculator
Elastic energy stored in a loaded bar — and what it means when it lets go. The calculation implements U = ½Pδ = P²L/2AE (Castigliano / energy methods). A tensioned rock-bolt or crane rope is a loaded spring — this number is the bang when it snaps. Long slender bolts absorb shock better than short fat ones: same stress, more joules.
How to use Strain Energy Calculator
- 1Enter Force in kN.
- 2Enter Length in m.
- 3Enter Area in mm².
- 4Enter E in GPa.
- 5Read Stored energy, Extension instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Strain Energy Calculator?
- ✓Implements the standard formula — U = ½Pδ = P²L/2AE
- ✓Reference cited on-page: Castigliano / energy methods
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Strain Energy Calculator use?+
It computes U = ½Pδ = P²L/2AE, per Castigliano / energy methods. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
A tensioned rock-bolt or crane rope is a loaded spring — this number is the bang when it snaps. Long slender bolts absorb shock better than short fat ones: same stress, more joules.
Where do the material property defaults come from?+
Defaults are standard handbook values (ASM, manufacturer datasheets, the cited standard). Always substitute certified values from your material's test certificate for critical work.
Is the Strain Energy Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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