DENSITY OF SOIL IN PLACE BY THE SAND-CONE METHOD

 

SCOPE:

            This method of test is intended for determining the in-place density of soils. The apparatus described herein is restricted to the tests in soils containing particles not larger than 2” in diameter.

APPARATUS:

  1. Sand pouring Apparatus
  2. Standard sand-graded between the No.25 and No.52 B.S. Sieves.
  3. Soil tray with a central hole
  4. Balance of 15kg. capacity
  5. Sensitive balance accurate to 0.1gm.
  6. Oven

Miscellaneous equipments such as small pick, chisels or spoon for digging test hole, moisture tins.

PROCEDURE:

1.Density of Sand:

            Fill the Sand Pouring Apparatus with known mass of sand (M1) and place it concentrically on top of the calibrating cylinder. Open the shutter and allow sand to drain out. When no further movement of sand takes place in the apparatus close the shutter and weight the sand remaining in the apparatus (M2) (M1-M2) represent the quantity of sand used in filling calibrating cylinder as well as cone of the apparatus.

            Now [(M1-M2) – (W1-W2)] gives the mess of sand required to fill the calibrating cylinder. Volume (Vc) of the cylinder may be determined either by measuring its internal dimensions or by filling it with water.

            Density of sand can be computed using mess of sand filled in cylinder and volume (Vc) of the cylinder.

 

2. Weight of Sand Occupying the Cone of the Sand Pouring Apparatus:

            Pour sand into the apparatus with valve closed and determine weight of apparatus and sand (W1). Place the apparatus on a smooth glass plate and open the valve to fill the conical portion. After the sand stops running, close the valve sharply, and weight the remaining sand into the apparatus (W2).  (W1 – W2) represents the weight of sand required to fill the cone of the apparatus. Replace the sand removed in the apparatus.

 

3. Density of Soil:

            Prepare the surface of the location to be tested so that it is a level plane. Keep the soil tray firmly on the place surface. Excavate with hand tools a hole with diameter equal to that of the hole of the plate and about 10cm. in depth with smooth walls and rounded bottom edges. Place all loosened soil in a container being careful to avoid losing any material. Seat the already weighed apparatus with sand on the hole of the tray. Open the valve and after the sand has stopped flowing close the valve. Weigh the apparatus with remaining sand and determine the weight of sand occupying the cavity. Weigh the material that was removed from the test hole. Mix the material thoroughly and weigh a representative sample for moisture determination. Dry and weigh the sample to determine moisture content.

 

CALCULATIONS:

            From the known density of sand and the weight of sand occupying the hole, calculate the volume of hole.

            From the weight of the soil cooped out of hole whose volume is now known and the value of moisture content calculate the wet and dry density of soil.

 

Click here for: Sand-Cone Method Data Sheet