Concrete Reinforcement
Deterministic engineering intelligence platform for mechanical, structural, and electrical designers. 91 modules validated solvers, 3D CAD workspace, and ISO/DIN standards compliance.
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▸Formula · assumptions · example(ACI 318-19 · Eurocode 2 (EN 1992-1-1) · TS 500)
Formula
M_u = \phi A_s f_y \left(d - \frac{a}{2}\right), \quad a = \frac{A_s f_y}{0.85 f'_c b}
ACI 318 / Eurocode 2 ultimate flexural moment capacity and Whitney equivalent compressive rectangular stress block for reinforced concrete.
Assumptions
- · Bernoulli plane section hypothesis: strain varies linearly through depth of member
- · Concrete tensile strength neglected in ultimate flexural limit state design
- · Tension-controlled ductile section confirmed: tensile steel strain εt ≥ 0.005 (strength reduction factor φ = 0.90)
Worked example
Worked example — RC Beam (b = 250 mm, d = 450 mm, 3×Φ20 Rebar As = 942 mm², f'c = 30 MPa, fy = 420 MPa)
Depth of stress block a = 62.1 mm. Ultimate flexural moment capacity Mu = 142.1 kN·m with ductile tension failure mode.