RC Section Calculator

Calculate flexural and shear capacity of reinforced concrete beams online. Enter section dimensions, concrete strength, and rebar properties — free structural tool

Section Properties

Beam Width b (mm)

Effective Depth d (mm)

Concrete Strength fc' (N/mm²)

Rebar Yield fy (N/mm²)

Rebar Area As (mm²)

Shear Reinforcement

Stirrup Area Av (mm²)

Stirrup Spacing s (mm)

Design Demand

Design Moment Mu (kN·m)

Design Shear Vu (kN)

Flexural Capacity

φMn

215.8 kN·m

239.7 kN·m

85.7 mm

Reinforcement Ratio ρ	1.013%
Balanced Ratio ρb	3.191%
Classification	Under-reinforced (Safe)

Capacity/Demand Ratio1.08

Shear Capacity

φVn

185.5 kN

247.4 kN

124.9 kN

122.5 kN

Capacity/Demand Ratio1.24

Formulas

a = As × fy / (0.85 × fc' × b)

Mn = As × fy × (d - a/2)

Vc = 0.17 × √fc' × b × d

Vs = Av × fy × d / s

Vn = Vc + Vs