Kern / Middle-Third Eccentricity Checker
Is the resultant inside b/6? No-tension check for footings, dams and masonry.
Keep the resultant in the middle third and the bearing diagram stays trapezoidal — the rule that shaped every gravity dam and masonry pier since the Romans (empirically).
Formula
Kern / Middle-Third Eccentricity Checker is a free middle third rule for structural engineers, fabricators and site engineers — 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 Kern / Middle-Third Eccentricity Checker
Is the resultant inside b/6? No-tension check for footings, dams and masonry. The calculation implements no tension when e ≤ b/6 (the middle third) (Gravity structure design — middle third rule). Keep the resultant in the middle third and the bearing diagram stays trapezoidal — the rule that shaped every gravity dam and masonry pier since the Romans (empirically).
How to use Kern / Middle-Third Eccentricity Checker
- 1Enter Load eccentricity e in mm.
- 2Enter Section/footing width b in mm.
- 3Read Kern limit b/6, e / (b/6) instantly — no submit button needed.
- 4Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Kern / Middle-Third Eccentricity Checker?
- ✓Implements the standard formula — no tension when e ≤ b/6 (the middle third)
- ✓Reference cited on-page: Gravity structure design — middle third rule
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Built-in engineering verdict flags out-of-range results instantly
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Kern / Middle-Third Eccentricity Checker use?+
It computes no tension when e ≤ b/6 (the middle third), per Gravity structure design — middle third rule. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
Keep the resultant in the middle third and the bearing diagram stays trapezoidal — the rule that shaped every gravity dam and masonry pier since the Romans (empirically).
Can I use this for real structural design?+
It implements the exact textbook/code formula cited below the result and is ideal for sizing, checking and learning. Final designs should be verified by a qualified engineer against the full code with all load cases.
Is the Kern / Middle-Third Eccentricity Checker 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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