Analysis & loading · Load take-down & combinations
Load combinations (AS/NZS 1170.0) calculator
Strength and serviceability combinations for any action effect (moment, shear, axial or reaction) from dead, imposed, wind, earthquake and snow, with the governing case.
Standard: AS/NZS 1170.0 Cl 4.2.2 strength · Cl 4.3 serviceability · Table 4.1 ψ
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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 |
|---|---|---|
| Permanent action effect G | 10 | |
| Imposed action effect Q | 5 | |
| Ultimate wind effect Wu (signed) | -8 | |
| Serviceability wind effect Ws | -4 | |
| Earthquake effect Eu | 2 | |
| Snow effect Su | 0 | |
| Occupancy (ψ factors) | Residential / office floors (ψs 0.7, ψl 0.4, ψc 0.4) |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| ULS 1.35G | 13.500 | |
| ULS 1.2G + 1.5Q | 19.500 | |
| ULS 1.2G + 1.5ψl·Q | 15.000 | |
| ULS 1.2G + ψc·Q + Wu | 6.000 | |
| ULS 0.9G + Wu | 1.000 | |
| ULS G + ψc·Q + Eu | 14.000 | |
| ULS G + ψc·Q − Eu | 10.000 | |
| ULS 1.2G + ψc·Q + Su | 14.000 | |
| SLS G + ψs·Q (short-term) | 13.500 | |
| SLS G + ψl·Q (long-term) | 12.000 | |
| SLS G + Ws | 6.000 | |
| Governing ULS maximum | 19.500 (1.2G + 1.5Q) | |
| Governing ULS minimum | 1.000 (0.9G + Wu) |
Method, formulas and assumptions
- ψs = 0.7, ψl = 0.4, ψc = 0.4 (Residential / office floors, AS/NZS 1170.0 Table 4.1)
- Enter effects with their signs (e.g. wind uplift negative). Earthquake is checked in both directions
- Add 0.9G combinations for stability (overturning, uplift) as shown; use the governing pair for design
- Other combinations (e.g. 1.35G with prestress, liquid pressure, fire) are outside this tool
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.