EngineeringToolkit

Reinforced Concrete Beam Capacity Formula

The nominal moment capacity of a reinforced concrete beam.

Formula

Mn = As · fy · (d - a/2)

Discipline: Civil Engineering. Result unit: N·m.

Variables and units

  • Mn — Moment Capacity (N·m): Nominal moment capacity
  • As — Steel Area (m²): Area of tension reinforcement
  • fy — Steel Yield Stress (Pa): Yield stress of steel
  • d — Effective Depth (m): Effective depth of beam
  • a — Equivalent Stress Block Depth (m): Depth of equivalent stress block