low D90/D10 = good drainage
| Category | Diameter (mm) | % Retained |
| Stones | > 8.00 | 0.0 |
| Coarse Gravel | 8.00 - 4.00 | 0.0 |
| Fine Gravel | 4.00 - 2.00 | 0.0 |
| Very Coarse Sand | 2.00 - 1.00 | 0.0 |
| Coarse Sand | 1.00 - 0.50 | 4.2 |
| Medium Sand | 0.50 - 0.25 | 66.0 |
| Fine Sand | 0.25 - 0.125 | 27.5 |
| Very Fine Sand | 0.125 - 0.063 | 1.8 |
| Silt/Clay | < 0.063 | 0.5 |
Histogram showing % retained (including half octave sieves) |
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Graph showing % passing cumulative (including half octave sieves) |
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To calculate D90/D10 ratio (Gradation Index) |
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| D Values | ||||||||||||||||||||||||
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| D90/D10 = | 440 | = 2.4 | ||||||||||||||||||||||
| 187 | ||||||||||||||||||||||||
The D90/D10 value is an indication as to the uniformity of the distribution of particle sizes, hence its potential for interpacking.
The D50 value (median particle diameter) is used to give a general indication as to the coarseness of a material. D50 values from 200-500 microns are generally found in sportsturf rootzones, sands and top dressings.
