Reinforced concrete beam calculator (Eurocode 2)

Set the beam width, effective depth, bars and concrete strength to get the neutral axis depth, lever arm and moment of resistance, and whether the section is under-reinforced.

Works in metric or imperial units.

Learn reinforced concrete properly

StudyAI writes clear notes on any topic you study, with practice quizzes, past-paper questions explained, and interactive models like this one in the notes.

Get free notes and a quiz on this
Free to start. No card needed.

Questions students ask

How do you find the moment of resistance of an RC beam?

With the simplified Eurocode 2 stress block: x = 0.87fykAs/(0.567fck × b × 0.8), z = d − 0.4x and MRd = 0.87fykAs z.

Why should x/d be at most 0.45?

It keeps the section under-reinforced, so the steel yields and the beam deflects visibly before the concrete crushes.

Free notes on reinforced concrete

More civil tools

Compaction test calculator: OMC and MDD
Enter Proctor test results to get dry density, the compaction curve, optimum moisture content (OMC), maximum d…
Sieve analysis calculator: D10, D30, D60, Cu, Cc
Enter masses retained on each sieve to get % passing, the grading curve, D10, D30, D60, Cu and Cc, and whether…
Soil phase diagram calculator
From bulk density, moisture content and Gs get void ratio, porosity, degree of saturation and dry density, wit…
Beam deflection calculator with SFD and BMD
Simply supported or cantilever beam with a point or uniform load: reactions, shear force and bending moment di…
All interactive tools
Use this on your own site or class page

Copy this code. It is free to use, as long as the link stays.