Field Density Test Service
A. Rubber-Balloon Method
1. Position the density plate on a flat surface and set the volume measuring apparatus in the recessed hole in the density plate.
2. Hold the apparatus down firmly in position, open the control valve, pump the balloon down with the rubber bulb until the water level in the graduated cylinder has reached its lowest position, and record this volume which is the initial reading.
3. Pump the balloon back into the cylinder by inverting the rubber bulb, and close the control valve.
4. Place the density plate in a level position on the material to be tested, dig a test hole about 4 in. in diameter and 4 in. deep, retain all the material which is removed from the hole, then measure and record the mass of the excavated soil.
5. Set the apparatus in the recess in the density plate, hold it down firmly, open the control valve, pump the balloon into the hole, and record the lowest point reached by the water in cylinder which is the final reading.
6. Invert the pressure-vacuum bulb and pump the balloon back into the cylinder.
7. Subtract the initial reading from the final reading and obtain the volume of the hole in cubic feet.
8. Mix the material thoroughly and secure a representative sample of not less than 100 gm for moisture determination.
9. Make density calculations based on volume of the test hole and dry or wet weight (as required) of materials removed.
B. Sand-Cone Method
1. Place the empty sand-cone apparatus upright on a firm level surface, close the valve and fill the funnel with sand.
2. Open valve and, keeping funnel at least half full of sand, fill the apparatus.
3. Close the valve sharply, empty excess sand, and weigh.
4. Determine the weight of sand required to fill the funnel by seating the inverted apparatus on a plane surface, opening the valve until the sand stops running, closing the valve sharply and weighing. (When the base plate is used it should be considered a part of the funnel).
5. Replace the sand removed in the funnel determination, close the valve and weigh.
6. Seat the density plate, if any, on the test hole, center the sand-cone apparatus, open the valve and, after the sand has stopped flowing, close the valve.
ึ7. Weigh the apparatus with remaining sand.
8. Determine the volume of the jar and attachment up to and including the valve orifice by weighing the empty apparatus, filling with water until it appears over the valve, weighing the filled apparatus, and measuring the temperature of the water.