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Propped Cantilever — UDL Calculator

One end fixed, one propped: reactions, max moment and deflection.

0
Max deflection (mm)
0
Max bending moment (kN·m)
0
Max reaction (kN)

The prop carries 3/8 of the load and the fixed end 5/8 — the first indeterminate structure every student solves.

Formula

R_prop = 3wL/8; M_max = wL²/8 (at fixed end); δ ≈ wL⁴/185EI
References: Roark's Formulas for Stress and Strain; AISC Steel Manual beam tables

Propped Cantilever — UDL Calculator is a free propped cantilever 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 Propped Cantilever — UDL Calculator

One end fixed, one propped: reactions, max moment and deflection. The calculation implements R_prop = 3wL/8; M_max = wL²/8 (at fixed end); δ ≈ wL⁴/185EI (Roark's Formulas for Stress and Strain; AISC Steel Manual beam tables). The prop carries 3/8 of the load and the fixed end 5/8 — the first indeterminate structure every student solves.

How to use Propped Cantilever — UDL Calculator

  1. 1Enter Load intensity w in kN/m.
  2. 2Enter Span L in m.
  3. 3Enter Elastic modulus E in GPa (Steel 200 · concrete 25–30 · timber 11 · aluminium 69).
  4. 4Enter Moment of inertia I in cm⁴ (ISMB 250 ≈ 5,131 cm⁴ · 230×450 RC ≈ 17,500).
  5. 5Read Max deflection, Max bending moment, Max reaction instantly — no submit button needed.
  6. 6Need US units? Flip the SI/Imperial toggle and every field converts.

Why use Propped Cantilever — UDL Calculator?

  • Implements the standard formula — R_prop = 3wL/8; M_max = wL²/8 (at fixed end); δ ≈ wL⁴/185EI
  • Reference cited on-page: Roark's Formulas for Stress and Strain; AISC Steel Manual beam tables
  • One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
  • Runs entirely in your browser — nothing uploaded, free forever

Frequently asked questions

What formula does the Propped Cantilever — UDL Calculator use?+

It computes R_prop = 3wL/8; M_max = wL²/8 (at fixed end); δ ≈ wL⁴/185EI, per Roark's Formulas for Stress and Strain; AISC Steel Manual beam tables. The formula is displayed under the result.

What should I keep in mind when using this calculator?+

The prop carries 3/8 of the load and the fixed end 5/8 — the first indeterminate structure every student solves.

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 Propped Cantilever — UDL 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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