ACI AGGREGATE TESTING TECHNICIAN LEVEL
1 SAMPLE WRITTEN EXAM QUESTIONS WITH
CORRECT ANSWERS VERIFIED
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
5. The Los Angeles Machine consists of a hollow ____________, with an
opening for the introduction of the test sample, a dust-tight ______,
and a ___________ shelf. Answer: Steel cylinder; cover; removable steel
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
6. A shelf of wear-resistant steel, rectangular in cross section, and
mounted on the cover, is preferred. True or False? Answer: False, a
shelf mounted independently of the cover is preferred.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
7. A _________ , __________ speed must be maintained. Answer: Uniform,
peripheral
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
,8. The steel spheres should be 31.8 mm (1-1/4 in.) in diameter and
have a mass of 320 g. True or False? Answer: False; they should
average 46.8 mm (1-27/32 in.) and have a mass between 390 and
445 g.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
9. If grading B is used, ____ spheres are needed. Answer: 11
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
10. After the test sample and steel spheres are in the machine, rotate
the drum at __ to __ r/min. for ____ revolutions. Answer: 30-33 r/min
for 500 revolutions.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
11. After the required revolutions, separate the material using a
______________ Answer: 1.70 mm sieve (No. 12 sieve)
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
,12. The _______ material that remains after sieving, should be oven-
dried to ______ Answer: Coarse; substantially constant mass
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
13. Computing the ratio of loss after 100 revolutions to the loss after
500, may offer valuable information regarding the uniformity of the
test sample. True or False? Answer: True
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
14. The difference between the original mass of the test sample and
the final mass should be reported as a percent of the
___________________ . This is the percent loss. Answer: Original mass
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
15. The results of properly conducted tests run by different
laboratories on the same coarse aggregates are not expected to
differ by more than ____ % of their average. Answer: 12.7
◉ ASTM C535 LA Machine Large-Size Course Agg.
, 1. This test method covers all aggregate larger than 10 mm (3/8 in.).
True or False? Answer: False; larger than 19 mm (3/4 in.)
◉ ASTM C535 LA Machine Large-Size Course Agg.
2. This test relies on the rotation of a ______ drum containing 12 ______
spheres to abrade and grind aggregate. Answer: Steel; steel
◉ ASTM C535 LA Machine Large-Size Course Agg.
3. The number of revolutions of the drum is immaterial providing
that the operator runs the machine for 30 min. True or False?
Answer: False, the number of revolutions is prescribed to provide
valid test results.
◉ ASTM C535 LA Machine Large-Size Course Agg.
4. This test indicates the relative __________ or __________ of different
aggregate sources which have similar mineral composition. Answer:
Quality; Competence
◉ ASTM C535 LA Machine Large-Size Course Agg.
1 SAMPLE WRITTEN EXAM QUESTIONS WITH
CORRECT ANSWERS VERIFIED
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
5. The Los Angeles Machine consists of a hollow ____________, with an
opening for the introduction of the test sample, a dust-tight ______,
and a ___________ shelf. Answer: Steel cylinder; cover; removable steel
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
6. A shelf of wear-resistant steel, rectangular in cross section, and
mounted on the cover, is preferred. True or False? Answer: False, a
shelf mounted independently of the cover is preferred.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
7. A _________ , __________ speed must be maintained. Answer: Uniform,
peripheral
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
,8. The steel spheres should be 31.8 mm (1-1/4 in.) in diameter and
have a mass of 320 g. True or False? Answer: False; they should
average 46.8 mm (1-27/32 in.) and have a mass between 390 and
445 g.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
9. If grading B is used, ____ spheres are needed. Answer: 11
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
10. After the test sample and steel spheres are in the machine, rotate
the drum at __ to __ r/min. for ____ revolutions. Answer: 30-33 r/min
for 500 revolutions.
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
11. After the required revolutions, separate the material using a
______________ Answer: 1.70 mm sieve (No. 12 sieve)
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
,12. The _______ material that remains after sieving, should be oven-
dried to ______ Answer: Coarse; substantially constant mass
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
13. Computing the ratio of loss after 100 revolutions to the loss after
500, may offer valuable information regarding the uniformity of the
test sample. True or False? Answer: True
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
14. The difference between the original mass of the test sample and
the final mass should be reported as a percent of the
___________________ . This is the percent loss. Answer: Original mass
◉ AASHTO T 96 LA Machine Small-Size Course Agg.
15. The results of properly conducted tests run by different
laboratories on the same coarse aggregates are not expected to
differ by more than ____ % of their average. Answer: 12.7
◉ ASTM C535 LA Machine Large-Size Course Agg.
, 1. This test method covers all aggregate larger than 10 mm (3/8 in.).
True or False? Answer: False; larger than 19 mm (3/4 in.)
◉ ASTM C535 LA Machine Large-Size Course Agg.
2. This test relies on the rotation of a ______ drum containing 12 ______
spheres to abrade and grind aggregate. Answer: Steel; steel
◉ ASTM C535 LA Machine Large-Size Course Agg.
3. The number of revolutions of the drum is immaterial providing
that the operator runs the machine for 30 min. True or False?
Answer: False, the number of revolutions is prescribed to provide
valid test results.
◉ ASTM C535 LA Machine Large-Size Course Agg.
4. This test indicates the relative __________ or __________ of different
aggregate sources which have similar mineral composition. Answer:
Quality; Competence
◉ ASTM C535 LA Machine Large-Size Course Agg.
