The sand cone method is used for field density test in highway construction. In the field, the dry density test is performed to check the compaction of layers. Compaction is most beneficial for the preparation of sub base grade and different pavement layers and in the production of embankment in order to increase the steadiness and to lower settlement. In field compaction, the compacting moisture content is first controlled at ideal moisture content and the adequacy of rolling or compaction is controlled through testing the dry density accomplished and comparing with the maximum dry density.
Base layer-98%
Sub base layer-98%
Type 1 layer-95%
ABC layer-100%
Road shoulder- 98%
Testing procedure
The weight of empty sand cone is estimated and after that loaded with dry sand and weighted. The dirt exhumed from the gap is gathered and weighted. Subsequent to weighting, an example of soil is taken to decide its water content. The sand cone is set on the test hole with the assistance of the base plate and sand is permitted to keep running by opening the control value.
At the point when the sand stop running, the valve is shut and the cone is weighted with the rest of the sand. At that point, the dry density of soil can be measured and the present of otherwise of the compaction is a failure. At that point, the compacted place to be re-compacted and re-test.
Calculation
The volume of the hole = Mass of sand in hole/Density of used sand.
Wet density = Mass of wet excavated soil/Volume of hole
Dry density = Wet density × 100%/ Moisture content of soil + 100
Degree of compaction = Dry density × 100%/Maximun dry density
- Weight of used sand: 16000mg
- Remain sand weight: 4286mg
- Density of sand: 1.349mg/cm3
- Weight of ABC: 15632.42mg
- Volume of cone: 2274cm3
- Volume of hole: 8683.47cm3
- Density of ABC: 2.48mg/cm
- Moisture content: 4.5%
- Dry density: 2.33mg/cm3
- Degree of compaction: 98%
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