How to perform the density test of field
The sand cone method is a useful test method that is generally undertaken to find out in-place density of compacted soils in a field. This method is ideal for any highway construction. In the jobsite, the dry density test is done for analyzing the highest dry density as well as the finest moisture content of soil with the use of heavy compaction following IS: 2720.
The density of the compacted soil derived from the sand-cone method is assumed to be perfect, in case the calibration container comprises of nearly the equivalent size or volume and facilitates the sand to drop to almost the equivalent height as a test hole in the field.
Compaction is mostly applied for developing the sub base grade and other pavement layers and in building up embankment with the aim of enhancing the strength and reducing settlement. In field compaction, initially the compacting moisture content is managed at optimal moisture content and the tolerability of rolling or compaction is managed by evaluating the dry density attained and comparing with the extreme dry density.
Base layer-98%
Sub base layer-98%
Type 1 layer-95%
ABC layer-100%
Road shoulder- 98%
Testing Method:
The weight of empty sand cone is calculate and then loaded with dry sand and weighted.
The soil extracted from the hole is assembled and weighted.
After checking the weight, the water content of soil is checked by taking a sample of soil.
With the use of base plate, the sand cone is arranged on the test hole and sand is authorized to run by opening the control value.
As soon as the sand pauses to run, the valve is closed and the cone is weighted through the left over sand.
Then the dry density of soil can is estimated and the present of compaction of otherwise the compaction is failure. Then, the compacted place should be re-compacted and re-tested.
Weight of applied 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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