How do I simulate a bridge girder?

Open this page and use the live Concrete Beam tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.

Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.

Can I use my own numbers?

Absolutely — every input is adjustable, and with data import you can drive a bridge girder from your own measurements.

Use case · powered by Concrete Beam

Concrete Beam for a bridge girder

Simulate a bridge girder live in your browser. This runs the real Concrete Beam solver — adjust the inputs, watch it respond instantly, and export the result. No install, no account.

For:Students Researchers Educators Engineers Hobbyists & Makers K-12 Students First Responders

Reinforced Concrete BeamLive

flexural capacity (ACI)

Controls

Presets

Width b (mm)

Effective depth d (mm)

Steel area As (mm²)

Concrete f'c (MPa)

Steel fy (MPa)

A reinforced concrete beam resists bending through a compression block in the concrete and tension in the steel. Setting these forces equal gives the stress-block depth a, and the moment capacity Mn = As·fy·(d − a/2). A tension-controlled section (steel yields first) fails gradually — the ductile behavior codes require. Educational tool, not a design.

▶ Run in Python

Data Inspector

Stress block a82 mm

Nominal Mn289 kN·m

Design φMn260 kN·m

Behaviortension-controlled

Governing equation

a = \frac{A _{s} f _{y}}{0.85 f _{c}^{'} b} = 82 mm, M_{n} = A_{s} f_{y} (d - \frac{a}{2}) = 1500 \cdot 420 (500 - \frac{82}{2}) = 289 kN\cdotm

Reading this result: Tension-controlled: with ρ ≈ 0.0100 well under 0.75·ρ_bal the steel yields first and the beam warns before it fails, while Mn = As·fy·(d − a/2) rises almost linearly with steel here.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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About this simulation

The full Concrete Beam tool models a bridge girder with the same numerics engineers and scientists use — running entirely client-side. Change any parameter and the result updates in real time, so you can build intuition, check a design, or teach the concept without spreadsheets or installs.

More you can do with Concrete Beam

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Other ways to simulate a bridge girder

2D Fluid (CFD) for a bridge girder 3D CFD for a bridge girder 3D FEA Space Frame for a bridge girder FEA Truss for a bridge girder Meshing + BCs for a bridge girder RLC Circuit for a bridge girder

Frequently asked questions

How do I simulate a bridge girder?: Open this page and use the live Concrete Beam tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.
Is it free?: Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.
Can I use my own numbers?: Absolutely — every input is adjustable, and with data import you can drive a bridge girder from your own measurements.