Concrete · Slabs & post-tensioning
Slab punching shear (AS 3600) calculator
Critical shear perimeter at dom/2, concrete capacity fcv, and moment-transfer reduction for an interior, edge or corner column.
Standard: AS 3600-2018 Cl 9.3 · interior, edge or corner column
Inputs in the worked example
The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.
| Input | Value | Unit |
|---|---|---|
| Column dimension c1 | 450 | mm |
| Column dimension c2 | 450 | mm |
| Mean effective depth dom | 220 | mm |
| f′c | 40 | MPa |
| Prestress σcp | 0 | MPa |
| V* | 650 | kN |
| Unbalanced M*v | 40 | kN·m |
| Column position | Interior |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Critical perimeter u | 2,680 | mm |
| βh | 1.00 | |
| fcv | 2.150 | MPa |
| Vuo | 1,268 | kN |
| Vu (with M*v) | 1,112 | kN |
| φVu (φ = 0.7) | 779 | kN |
| Utilisation | 0.835 |
- ✓ V* ≤ φVu — 0.83
Method, formulas and assumptions
- fcv = 0.17(1 + 2/βh)√f′c ≤ 0.34√f′c
- Vuo = u·dom(fcv + 0.3σcp)
- Vu = Vuo / [1 + u M*v / (8 V* a dom)]
- Edge and corner perimeters are simplified to three and two sides
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.