Slab design tool

RC Slab Design Quick Tool

Limit State Design Workflow complying with IS 456 : 2000

🛠️ Design Inputs

Clear Span Short ($L_x$) (m)

Clear Span Long ($L_y$) (m)

Support Condition Simply Supported Continuous Cantilever

Support Width (mm)

Grade ($f_{ck}$) M20 M25 M30

Steel ($f_y$) Fe 415 Fe 500

Overall Depth (mm)

Clear Cover (mm)

Live Load (kN/m²)

Floor Finish (kN/m²)

Main Bar Ø (mm)

Dist Bar Ø (mm)

Step 1 & 2: Structural Configuration

-

Aspect Ratio (Ly/Lx) = -

Effective Span ($L_{e}$): -

Step 3: Loading Metrics

- kN/m²

DL: - | LL: -

Factored Load ($W_u$): -

Design & Serviceability Controls

Step 4 & 10: Deflection (L/d)

-

Max Allowed: - | Actual: -

Step 5: Bending Moment ($M_u$)

-

Calculated across span

Step 8: Shear Safety

-

τ_v: - | τ_c: -

🧱 Step 6 & 7: Reinforcement Detailing b = 1000mm strips

Main Reinforcement

Required $A_{st}$: -

Minimum Allowed $A_{st}$: -

Recommended Layout: -

Distribution Reinforcement

Minimum $A_{st}$: -

Temp / Shrinkage Control: 0.12% Total Area

Recommended Layout: -

📋 Structural Notes & Detailing Rules (IS 456)

• Clear Cover: Checked at -. Ensure ≥ 15 mm structural baseline (20 mm recommended for exposed surfaces).
• Max Spacing Constraints: Main steel spacing cannot exceed $3d$ or $300\text{ mm}$. Distribution steel cannot exceed $5d$ or $450\text{ mm}$.
• Shear Verification: Slabs are safe without structural shear loops when nominal stress ($\tau_v$) is below concrete capacity ($\tau_c$).