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 non-mechanical 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
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Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
6.2 Quartering
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Civil Engineering Department
CE405 - Construction Materials and Testing Laboratory Manual
7. Observation
8. Conclusion:
9. Assessment:
CRITERIA
BEGINNER
1
ACCEPTABLE
2
PROFICIENT
3
SCORE
I. Laboratory Skills
Manipulative Skills
Members do not
demonstrate needed
skills.
Experimental
Set-up
Members are unable to
set-up the materials.
Process Skills
Members do not
demonstrate targeted
process skills.
Safety Precautions
Members do not follow
safety precautions.
II. Work Habits
Time Management /
Conduct of
Experiment
Members occasionally
demonstrate needed skills
Members always demonstrate
needed skills.
Members are able to setup the materials with
supervision.
Members occasionally
demonstrate targeted
process skills.
Members follow safety
precautions most of the
time.
Members are able to set-up the
material with minimum
supervision.
Members do not finish on
time with incomplete data.
Members 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.
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 require
supervision by the
teacher.
Other Comments/Observations:
Ability to do
independent work
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
𝑅𝑎𝑡𝑖𝑛𝑔 =
(𝑇𝑜𝑡𝑎𝑙 𝑆𝑐𝑜𝑟𝑒)
× 100
24
10. Reference(s):
ASTM C 702-98 “Standard Practice for Reducing Samples of Aggregate to Testing Size”
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