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Free and premium calculators for civil, structural and geotechnical engineers, contractors, surveyors and other technical professionals.
Simply Supported BeamConcrete VolumeEngineering Unit Converter
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Simply Supported Beam
Reactions, shear force and bending moment diagrams for a simply supported beam with a point load and a full-span UDL. Optional elastic deflection.
Concrete Volume
Concrete volume for rectangular elements with wastage allowance, optional weight and a rounded-up order quantity.
Engineering Unit Converter
Convert length, area, volume, force, stress, moment, mass, density and pressure units using exact conversion factors.
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Cantilever Beam Analysis
Support reaction, fixed-end moment, shear and tip deflection for a cantilever with a point load and a full-length UDL, with PDF report.
RC beam flexural design
RC beam shear design
RC beam torsion design
RC column design
Steel beam bending resistance
Steel beam shear resistance
Steel column buckling
Steel beam deflection
Lateral torsional buckling
Steel connection and bolt checks
Weld capacity
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Engineering calculation examples
Simply supported beam: offset point load + UDL
L = 6 m, P = 20 kN @ a = 2 m, w = 5 kN/m
RA = 20×4/6 + 5×6/2 = 28.33 kN
RB = 20×2/6 + 5×6/2 = 21.67 kN
Mmax = 28.33×2 − 5×2²/2 = 46.67 kN·m (x = 2 m)
Concrete volume: pad footings
6 × (1.8 m × 1.8 m × 0.6 m), 5% wastage
V = 6 × 1.8 × 1.8 × 0.6 = 11.664 m³
With 5% = 12.247 m³ → order 12.5 m³ (0.5 m³ steps)
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Each calculator page states its method and, where a design code applies, the standard, edition and National Annex.
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