Two-Span Continuous Beam Calculator
Support and span moments for equal two-span continuous beam under UDL.
The middle support hogs wL²/8 — exactly the simple-span max — and carries 25% extra reaction. Top steel over supports is not optional.
Formula
Two-Span Continuous Beam Calculator is a free continuous beam 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 Two-Span Continuous Beam Calculator
Support and span moments for equal two-span continuous beam under UDL. The calculation implements M_support = wL²/8; M_span = 9wL²/128; R_centre = 1.25wL (Three-moment theorem; IS 456 Table 12 coefficients). The middle support hogs wL²/8 — exactly the simple-span max — and carries 25% extra reaction. Top steel over supports is not optional.
How to use Two-Span Continuous Beam Calculator
- 1Enter UDL w in kN/m.
- 2Enter Each span L in m.
- 3Read Support moment (hogging), Span moment (sagging), Centre support reaction instantly — no submit button needed.
- 4Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Two-Span Continuous Beam Calculator?
- ✓Implements the standard formula — M_support = wL²/8; M_span = 9wL²/128; R_centre = 1.25wL
- ✓Reference cited on-page: Three-moment theorem; IS 456 Table 12 coefficients
- ✓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 Two-Span Continuous Beam Calculator use?+
It computes M_support = wL²/8; M_span = 9wL²/128; R_centre = 1.25wL, per Three-moment theorem; IS 456 Table 12 coefficients. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
The middle support hogs wL²/8 — exactly the simple-span max — and carries 25% extra reaction. Top steel over supports is not optional.
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 Two-Span Continuous Beam 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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