DETERMINATION OF MOISTURE CONTENT
OBJECTIVE
The purpose of this test is to determine the moisture content (w) of a soil as a percentage of its dry
mass.
EQUIPMENT USED
a) Soil samples
b) Balances, one with an approximate capacity of 500g, accurate to 0.50g and a second one
with an approximate capacity of 200g, accurate to 10mg.
c) A drying oven capable of maintaining a temperature between 105oC and 110oC.
d) Sample containers (tares) of various sizes.
e) A desiccator containing a self-indicating agent for cooling of samples for the determination
of constants.
f) Spoon
PROCEDURE
a) Measure the mass of the empty tare and record it as m1
b) Add the wet soil sample into the tare and record the mass of the tare + wet soil as m2
c) Leave the soil to dry in the oven at a temperature between 105oC and 110oC for 24 hrs.
Record the mass of the tare and dry soil as m3
TEST RESULTS
Table of results
Tare number
Mass of empty tare (g)
Mass of tare + wet soil (g)
Mass of tare + dry soil (g)
Mass of dry soil (g)
Mass of water (g)
49B
281
681
618
337
63
AM16
281
681
613
332
68
ANALYSIS OF TEST RESULTS
Calculate the moisture content of the soil as a percentage of the dry soil from the
formula:
Percentage moisture content = (m2 - m3) / (m3 – m1) X 100%
Where m1
is the mass of the tare (g)
m2
is the mass of the tare + wet soil(g)
m3
is the mass of the tare + dry soil (g)
% moisture content of tare 49B
= (681 – 618) / (618 – 281) x 100%
= 18.7%
% moisture content of tare AM16
= (681 – 613) / (613 – 281) x 100%
=20.5%
POSSIBLE SOURCES OF ERRORS
-
Zero error when using the scale to measure the masses so one should make sure
that the scale is zeroed before taking any readings
CONCLUSION
From the experiment above it prove that the moisture content of the soil sample is in
in the range of 18 – 20%.