Design rectangular reinforced concrete beams for flexure and shear per ACI 318. Interactive stress block visualization, tension-controlled check, and demand-to-capacity ratios.
A complete flexure-and-shear design toolset for rectangular reinforced concrete beams.
Compute nominal and factored moment capacity using the Whitney rectangular stress block with automatic φ factor.
Calculate concrete and steel shear contributions Vc + Vs per ACI 318 Section 22.5 with stirrup sizing.
Whitney block depth a, neutral axis depth c, and tensile strain εt computed from strain compatibility.
Compare actual ρ to ρmin and ρmax limits with clear pass/fail indication.
Tension-controlled, transition, or compression-controlled classification based on εt at nominal strength.
Automatic As,min check per ACI 318 §9.6.1 using both √f′c and 1.4/fy criteria.
Size and space transverse reinforcement with maximum spacing limits and minimum Av/s requirements.
Input factored demand moment and shear directly, or derive from distributed and point loads on a span.
DCR reported per limit state (flexure, shear) with color-coded results and utilization summary.
Live cross-section with stress block, neutral axis, tension/compression zones, and reinforcement layout.
Full engineering calculation report with formulas, intermediate values, and ACI code references.
Export professional calculation reports to PDF for documentation, review, and project records.
Get from inputs to a complete beam design in four simple steps.
Enter beam width, depth, cover, bar sizes, and material strengths f′c and fy.
Provide factored demand moment and shear at the critical section of the beam.
Inspect φMn, φVn, stress block, section classification, and demand-to-capacity ratios.
Generate a professional calculation report with all inputs, results, code references, and graphics.
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