Site investigation · Laboratory: soil classification
Soil aggressivity to buried concrete & steel calculator
Exposure classification for concrete and steel piles from pH, sulfate, chloride and resistivity. Thresholds indicative; check the current AS 2159 tables.
Standard: AS 2159 Tables 6.4.2(C) & 6.5.2(C) (indicative)
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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 |
|---|---|---|
| Soil pH | 5.2 | |
| Sulfate (SO₄) in soil | 6200 | ppm |
| Chloride in soil | 2400 | ppm |
| Soil resistivity | 3200 | Ω·cm |
| Soil condition | A: high permeability, in groundwater |
Worked example — results
| Result | Value | Unit |
|---|---|---|
| Concrete score (0 non-aggr … 3 severe) | 1.00 | |
| Score after soil condition | 1.00 | |
| Concrete exposure | Mild | |
| Steel score | 1.00 | |
| Steel exposure | Mild |
- ✗ Concrete non-aggressive
- ✗ Steel non-aggressive
Method, formulas and assumptions
- Concrete score (0 non-aggr … 3 severe) = MAX(IF(6200<5000,0,IF(6200<=10000,1,IF(6200<=20000,2,3))),IF(5.2>5.5,0,IF(5.2>=4.5,1,IF(5.2>=4,2,3)))) = 1
- Score after soil condition = MAX(0,1-IF(1=2,1,0)) = 1
- Concrete exposure = CHOOSE(1+1,"Non-aggressive","Mild","Moderate","Severe") = Mild
- Steel score = MAX(IF(5.2>5,0,IF(5.2>=4,1,2)),IF(2400<5000,0,IF(2400<=20000,1,2)),IF(3200>5000,0,IF(3200>=2000,1,2))) = 1
- Steel exposure = CHOOSE(1+1,"Non-aggressive","Mild","Moderate+") = Mild
- Thresholds coded here are indicative ranges; confirm against the current edition of AS 2159 before specifying durability.
Related site investigation calculators
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For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.