Slab Design
One-way and two-way RC slab design per ACI 318-25 and ACI 318-19: Method 3 coefficients (9 cases), reinforcement with user-editable bar+spacing override and live φMn capacity verification (with tension-controlled εt-based φ reduction per §21.2.2), deflection (Branson Ie + edge-aware service moment + sustained-LL ψ + selectable Tabla 24.2.2 limit + Tabla 24.2.4.1.3 ξ multiplier), punching shear (with λ_s size factor, lightweight λ, stud rails per ACI 421.1), crack control. Live 3D model with column top reinforcement. 105 unit tests.
Templates
Start from a textbook setup, then edit.
Live 3D model
Drag to rotate · scroll to zoom · right-click drag to pan · choose what to color the slab by · toggle deformed shape
Loading 3D viewer…
Contour plots (2D)
Spatial distribution of moments and required reinforcement (Method 3 + shape reconstruction). Toggle Mx / My / As fields.
Geometry
Edge conditions
Set each edge to free / simply supported / fixed (continuous).
Materials
Loads
Deflection settings
ACI Tabla 24.2.2 limits + Tabla 24.2.4.1.3 ξ multiplier
Punching shear
Disabled — toggle on to add a column and compute vu / φ·vc.
Print report branding (your firm)
Optional. Add your firm logo and name — they appear on the PDF / printed report cover. Your logo is embedded in the report only; nothing is uploaded to a server.