Determination of water content by oven drying method



Theory

The water content may be defined as the ratio of the weight of water to dry weight of water to the dry weight of the solid as called water content.

W = Ww/Ws X 100

It is also expressed as the quantity of free water in a soil is necessary to controlling the compaction operation in the determining the consistency limit for calculating the stability in all kinds of earthwork and foundation.

Application

It is the fundamental parameter which affects the soil properties like degree saturation, density, shear strength consistency, compaction and consolidation. Water content is the most frequently determined characteristics. In almost all soil test determination of water content of a soil is the most useful properties.

Item required

1.      Soil sample
2.    Balance
3.    Container
4.    Oven desiccator


Diagram

OVEN MACHINE


Procedure

1.      Clean the container and its mass was found with lid. (m1)

2.   The required quantity of moist sample was taken in the container replaced the lid (m2)


3.   The container was kept in the oven with lid. The temperature was maintain in between 1050 c to 1100 c for about 24hrs.

4.    After 24hrs the container is taken out it closed with lid and cool it preferably in a desiccator.


5.   Weighted the container with dried soil sample and record the final mass (m3) in gm.

6.    The step 1 to 5 repeated for two more soil specimen for the sample.


7.     Average of the should be reported as a water content of the soil.

Precaution

1.      Always weight the container with lid.

2.    The soil specimen should be recorded after the test and should not be used in any other test.

3.    Immediately after removing the container from the oven close the lid.

4.    Weight the container after cooling.

5.   Keeping the container inside the indicator while cooling especially during rainy season.


OBS.
NO.
PARTICULARS
DETERMINATION NO.
1ST READING
2ND READING
01
Container no.
A
B
02
Mass of container m1 in gm
23 gms
23 gms
03
Mass of container with wet soil specimen m2 in gm
66 gms
37.3 gms
04
Mass of container with dry soil specimen m3 in gm
58 gms
34.8 gms
05
Mass of dry soil (m3 – m1) gm
8 gms
2.8 gms
06
Mass of moisture (m2 – m3) gm
35 gms
11.5 gms
07
Water content = m1 – m3 / m3 – m1    X  100
22.86 %
24.35 %
08
Average water content = w %
22.86 + 24.35 / 2
= 23.605 %



RESULT

The water content of the soil sample is found to be = 23.605 %