Steel · Connections: bolts & welds
Bolt in shear & ply bearing calculator
Single bolt shear capacity with threads in / excluded from shear planes, ply bearing and end tear-out; bolt category and size selectable.
Standard: AS 4100 Cl 9.3.2.1, 9.3.2.4
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 |
|---|---|---|
| Bolt size | M20 | |
| Bolt category | 8.8/S | |
| Shear planes with threads (nn) | 1 | |
| Shear planes without threads (nx) | 0 | |
| Lap reduction kr | 1 | |
| Ply grade | Grade 250 plate | |
| Ply thickness | 10 | mm |
| Edge distance in force direction | 35 | mm |
| Design shear per bolt V* | 60 | kN |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Bolt diameter df | 20.00 | mm |
| Bolt tensile strength fuf | 830.0 | MPa |
| Tensile stress area As | 245.0 | mm² |
| Core area Ac (threads) | 225.0 | mm² |
| Shank area Ao | 314.0 | mm² |
| Plate yield stress fy (AS/NZS 3678) | 260.0 | MPa |
| Plate tensile strength fu | 410.0 | MPa |
| φVf = 0.8·0.62 fuf kr (nn Ac + nx Ao) | 92.63 | kN |
| φVb = 0.9·3.2 df tp fup | 236.2 | kN |
| φVp = 0.9 ae tp fup (tear-out) | 129.2 | kN |
| Design capacity | 92.63 | kN |
| Governing mode | bolt shear |
- ✓ V* ≤ φV
- ✓ Edge distance ≥ 1.5 df (sheared edge guide)
Method, formulas and assumptions
- Bolt diameter df = CHOOSE(3,12,16,20,24,30,36) = 20 mm
- Bolt tensile strength fuf = IF(2=1,400,830) = 830 MPa
- Tensile stress area As = CHOOSE(3,84.3,157,245,353,561,817) = 245 mm²
- Core area Ac (threads) = CHOOSE(3,76.2,144,225,324,519,759) = 225 mm²
- Shank area Ao = CHOOSE(3,113,201,314,452,707,1018) = 314 mm²
- Plate yield stress fy (AS/NZS 3678) = CHOOSE(1,IF(10<=8,280,IF(10<=12,260,250)),IF(10<=8,320,IF(10<=12,310,IF(10<=20,300,280))),IF(10<=12,360,IF(10<=20,350,340))) = 260 MPa
- Plate tensile strength fu = CHOOSE(1,410,430,450) = 410 MPa
- φVf = 0.8·0.62 fuf kr (nn Ac + nx Ao) = 0.8*0.62*830*1*(1*225+0*314)/1000 = 92.628 kN
- φVb = 0.9·3.2 df tp fup = 0.9*3.2*20*10*410/1000 = 236.16 kN
- φVp = 0.9 ae tp fup (tear-out) = 0.9*35*10*410/1000 = 129.15 kN
- Design capacity = MIN(92.628,236.16,129.15) = 92.628 kN
- Governing mode = IF(92.628=92.628,"bolt shear",IF(92.628=236.16,"ply bearing","tear-out")) = bolt shear
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.