Dry density of soil by core cutter method
Objective :
To determine the field or in-situ density of soil by the core cutter method.
Apparatus used :
Core cutter, Rammer, Weighing scale, Container etc.
Description The bulk density of soil can be defined as ratio of the weight of the soil to its corresponding volume and, it is also called in-situ density. It is expressed in g/cm3. Bulk density is needed for the determination of the safe bearing capacity of the soil for the purpose of stability analysis of slopes, settlement calculation and also to determine the pressure on the underlying strata.
Measure the height and the diameter of the core cutter to calculate the volume of the core cutter.
Internal Height of the core cutter, H= _____ cm
Internal Diameter of the core cutter, D = _____ cm
Volume of the core cutter = _____ cm3
Volume of the core cutter =
cc
✔
✘
Measure the weight of the core cutter by using weighing balance.
Weight of the core cutter (W1) = _____ g
Clean and level the soil to be tested and place the core cutter over it.
Fix the Rammer on the core cutter.
Start pressing the core cutter in the soil using Rammer.
Remove the core cutter from the soil carefully without disturbing the sample inside the core cutter.
Measure the weight of the soil in the core cutter.
Weight of the empty container, (w1) = _____ g
Observations:
| Trial No. | 1 |
| Weight of core cutter, (W1) | |
| Weight of core cutter + soil, (W2) | |
| Weight of soil, (W)=(W2-W1) | |
| Volume of soil, (V) |
Calculations:
| Bulk density, ρb = | W⁄V = g/cc |
Calculate the weight of the empty container.
Weight of the soil in the core cutter is (W2) = _____ g
Weight of the empty container is (w1) = _____ g
000.01
Remove the soil from the core cutter. Take a sample of the wet soil in the container and measure its weight.
Weight of the container with wet soil is (w2) = _____g
Place the container with wet soil in the oven for 24 hours at 110°C temperature.
After 24 hours
Repeat the procedure from step 7 - 10
Measure the weight of the container with dry soil.
Weight of the container with the dry soil (w3) = _____ g
000.01
Observations:
| Container number | |
| Weight of container, w1 | |
| Weight of container + wet soil, w2 | |
| Weight of container + dry soil, w3 | |
| Weight of water, ww=w2-w3 | |
| Weight of dry soil, ws=w3-w1 | |
| Weight of wet soil, ρb |
Calculations:
| Water content, W = | w2-w3⁄w3-w1 x 100 |
| = | % |
| Dry Density, ρdry = | ρb⁄1+W = g/cc |
Repeat the procedure from step 8 - 11
Result:
| Trial No. | Weight of Core cuttter + soil, W1 (g) | Weight of soil, M (g) | Volume of soil, V (cm3) | Bulk density, ρb (g/cc) ρb = M⁄V | Weight of empty container, w1 (g) | Weight of empty container + Bulk soil, w2 (g) | Weight of empty container + dry soil, w3 (g) | Moisture content, W = w2-w3⁄w3-w1 % | Dry Density, ρdry (g/cc) ρdry = ρb⁄1+W |
Inference:
By observing the result from the experiment the type of soil is found to be heavy clay soil.
Trial =
