Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
Experiment No. I
SAMPLING OF AGGREGATES
1. Objective(s):
The activity aims to introduce the basic principle, significance and procedures for the sampling
of aggregates (Coarse and Fine Aggregates).
2. Intended Learning Outcomes (ILOs):
The students shall be able to:
2.1 Familiarize the basic instruments and apparatus used in reducing the field sample of
aggregates to test sample.
2.2 Determine the two methods specified by ASTM (i.e. Quartering and Mechanical Splitter)
2.3 Conduct the actually the experiment with full knowledge.
3. Discussion:
Sampling is the most important step in assuring the good quality of the aggregates. It is also
should be the first thing must be learned in studying construction materials and testing. As specified
in ASTM C 702-98 “Standard Practice for Reducing Samples of Aggregate to Testing Size” the two
methods used in practice are Method A (Mechanical Splitter) and Method B (Quartering). Method A
separates the sample into halves as the material passes through the spaces between the bars in
the splitter. Same number of particle size goes in each half of the splitter. Method B is a nonmechanical method of reducing a sample. The best method of reducing highly moistened
compacted aggregate.
4. Resources:
1 unit Mechanical Splitter
2 Pans
1 Weighing Scale
1 Bag of Coarse Aggregates
1 Scoop or spoon
1 Bag of Coarse Aggregates
5. Procedure:
For Mechanical Splitter
1. Place the sample in the pan and uniformly distribute it from edge to edge so that approximately
equal amounts flow through each chute. The rate at which the sample is introduced shall be
such as to allow free flowing through the chutes into the pans below.
2. Split the sample from one of the two pans as many times as necessary to reduce the sample to
the size specified for the intended test. The portion of the material collected in the other pan
may be reserved for reduction in size for other tests.
3. As check for effective splitting, determine the mass of each part of the split. If the ratio of the
two masses differs by more than 5 percent, corrective action must be taken.
For Quartering
1. Place the sample on a hard, clean, leveled surface where there will be neither loss of material
nor the accidental addition of foreign material.
2. Mix the material thoroughly by turning the entire sample over a minimum of three times. With
the last turning, shovel the entire sample into a conical pile by depositing each shovelful on top
of the preceding one.
3. Flatten the conical pile to a uniform thickness and diameter by pressing down with a shovel.
The diameter should be four to eight times the thickness.
4. Divide the flattened pile into four approximately equal quarters with a shovel or trowel.
5. Remove two diagonally opposite quarters, including all fine materials, and brush the cleared
spaces clean.
6. Successively mix and quarter the remaining material until the sample is reduced to the desired
size. The final test sample consists of two diagonally opposite quarters
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Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
Course:
Group No.:
Group Members:
Experiment No.:
Section:
Date Performed:
Date Submitted
Instructor:
6. Data and Results:
6.1 Mechanical Splitter
6.2 Quartering
7. Observation
8. Conclusion:
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Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
9. Assessment:
BEGINNER
1
CRITERIA
ACCEPTABLE
2
PROFICIENT
3
SCORE
I. Laboratory Skills
Manipulative
Skills
Experimental
Set-up
Process Skills
Safety
Precautions
II. Work Habits
Time
Management /
Conduct of
Experiment
Members
occasionally
demonstrate needed
skills
Members are unable Members are able to
to set-up the
set-up the materials
materials.
with supervision.
Members
Members do not
occasionally
demonstrate targeted
demonstrate targeted
process skills.
process skills.
Members do not
Members follow
follow safety
safety precautions
precautions.
most of the time.
Members do not
demonstrate needed
skills.
Members do not
finish on time with
incomplete data.
Cooperative
and Teamwork
Members do not
know their tasks and
have no defined
responsibilities.
Group conflicts have
to be settled by the
teacher.
Neatness and
Orderliness
Messy workplace
during and after the
experiment.
Ability to do
independent
work
Members require
supervision by the
teacher.
Other Comments/Observations:
Members finish on
time with incomplete
data.
Members have
defined
responsibilities most
of the time. Group
conflicts are
cooperatively
managed most of the
time.
Clean and orderly
workplace with
occasional mess
during and after the
experiment.
Members require
occasional
supervision by the
teacher.
Members always
demonstrate needed
skills.
Members are able to setup the material with
minimum supervision.
Members always
demonstrate targeted
process skills.
Members follow safety
precautions at all times.
Members finish ahead of
time with complete data
and time to revise data.
Members are on tasks
and have defined
responsibilities at all
times. Group conflicts
are cooperatively
managed at all times.
Clean and orderly
workplace at all times
during and after the
experiment.
Members do not need to
be supervised by the
teacher.
Total Score
(𝑇𝑜𝑡𝑎𝑙 𝑆𝑐𝑜𝑟𝑒)
𝑅𝑎𝑡𝑖𝑛𝑔 =
24
× 100
10. Reference(s):
ASTM C 702-98 “Standard Practice for Reducing Samples of Aggregate to Testing Size”
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Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
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