Steel · Bases, anchors & embedded plates
Column base plate (axial) calculator
Concrete bearing capacity with confinement and required plate thickness for a concentrically loaded column.
Standard: AS 3600 Cl 12.6 bearing · cantilever plate method (AISC DG1 form)
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 |
|---|---|---|
| Design axial N* | 1500 | kN |
| Column section | 250UC72.9 | |
| Plate width B | 400 | mm |
| Plate length N | 400 | mm |
| Pedestal / footing width | 800 | mm |
| Pedestal / footing length | 800 | mm |
| Concrete f'c | 25 | MPa |
| Plate fy | 250 | MPa |
| Plate thickness provided | 25 | mm |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| A1 plate area | 0.160 | m² |
| Confinement √(A2/A1) ≤ 2 | 2.00 | |
| Bearing capacity φN = 0.6·0.85f'c·A1·√(A2/A1) | 4,080 | kN |
| Cantilever m / n | 79 / 98 | mm |
| Required thickness | 28.4 | mm |
- ✓ N* ≤ concrete bearing φN
- ✗ Plate thickness ≥ required
- ✓ Plate larger than column
Method, formulas and assumptions
- Bearing (AS 3600 Cl 12.6): φ = 0.6, 0.85f'c·A1·√(A2/A1) ≤ 2 × 0.85f'c·A1
- m = (N − 0.95d)/2, n = (B − 0.8bf)/2
- t = l·√(2N*/(0.9·fy·B·N)) (cantilever plate under uniform bearing)
- Holding-down bolts, shear and moment transfer not checked
Related steel calculators
- Embedded plate with headed studs (anchor group) — Steel plate cast into a concrete element with a rectangular group of welded headed studs, loaded in tension…
- Fixed column base plate with anchor bolts — Axial load plus moment: stress-block length, anchor tension, bearing stress, and plate thickness on both the…
- Cast-in anchor: concrete cone & steel (simplified) — Characteristic cone breakout with projected-area group and edge factors, steel tensile failure, and design…
- Base plate shear lug — Lug embedded below grout: concrete bearing on the lug, lug cantilever bending and the lug-to-plate fillet…
- Steel beam (UB) — Section and member moment capacity (lateral-torsional buckling), shear and deflection, with built-in UB sizes.
- Steel angle lintel — Equal-angle lintel over a masonry opening with triangular (arching) or full masonry load.
For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.