ACI CONCRETE FIELD TESTING TECHNICIAN –
GRADE 1 | 250 Practice MCQs for Exam Preparation
2026
covering all key test procedures per ACI 318, ASTM standards, and ACI CP-1.
Summary of Topics Covered:
Sampling (ASTM C172) — Qs 1–10
Slump Test (ASTM C143) — Qs 11–25
Air Content Pressure Method (ASTM C231) — Qs 26–40
Air Content Volumetric Method (ASTM C173) — Qs 41–45
Unit Weight & Yield (ASTM C138) — Qs 46–55
Temperature (ASTM C1064) — Qs 56–62
Making & Curing Cylinders (ASTM C31) — Qs 63–75
Compressive Strength (ASTM C39) — Qs 76–82
Flexural Strength (ASTM C78/C293) — Qs 83–86
Mix Design & ACI 318 — Qs 87–100
Placement & Consolidation — Qs 101–115
Acceptance Criteria (ACI 318) — Qs 111–115
Concrete Materials & Properties — Qs 116–135
QC & Documentation — Qs 136–150
Additional Standards & Special Topics — Qs 151–250
SECTION 1: SAMPLING FRESH CONCRETE (ASTM C172)
,1. According to ASTM C172, composite samples of fresh concrete shall be obtained from not
less than _____ separate portions of the load.
A) One B) Two C) Three D) Five
C) Three (correct answer) Rationale: ASTM C172 requires that composite samples be
obtained from not fewer than three separate portions taken at regularly spaced intervals
during discharge of the middle portion of the load, to ensure a representative sample.
2. The time allowed to complete sampling and start tests for slump, air content, and temperature
is within _____ minutes after obtaining the final portion of the composite sample.
A) 3 B) 5 C) 10 D) 15
B) 5 (correct answer) Rationale: ASTM C172 specifies that sampling and the beginning of
tests must be completed within 5 minutes after obtaining the final portion of the composite
sample to ensure the concrete hasn't begun to stiffen or change properties.
3. According to ASTM C172, samples for acceptance testing should NOT be taken from the first
_____ or last _____ of the load.
A) 5%, 5% B) 10%, 10% C) 15%, 15% D) 20%, 10%
B) 10%, 10% (correct answer) Rationale: The first and last 10% of a concrete load are
excluded from sampling under ASTM C172 because these portions are not representative
of the middle, well-mixed portion of the batch.
4. The minimum size of a sample of fresh concrete taken for testing purposes according to
ASTM C172 should be at least:
,A) 1 cubic foot B) 0.5 cubic foot C) 1.5 cubic foot D) 0.25 cubic foot
A) 1 cubic foot (correct answer) Rationale: ASTM C172 specifies that the composite sample
must be at least 1 ft³ (28 L) to provide sufficient material for all required tests, ensuring
accuracy and representativeness.
5. Which of the following tools is NOT typically used when sampling concrete from a ready-mix
truck?
A) Wheelbarrow B) Sampling receptacle C) Vibrating table D) Shovel
C) Vibrating table (correct answer) Rationale: A vibrating table is used for consolidation
testing or making specimens in a lab setting. Sampling from a truck chute requires
receptacles, shovels, and a wheelbarrow to collect and combine the portions.
6. After obtaining a composite sample, the concrete should be remixed with a shovel for a
minimum of:
A) 10 seconds B) 30 seconds C) 1 minute D) 3 minutes
C) 1 minute (correct answer) Rationale: After collecting all portions of the composite
sample, ACI and ASTM guidelines require remixing for at least 1 minute to ensure
uniformity before performing any tests.
7. When sampling from a stationary mixer, samples are taken after discharging:
A) The first portion of the batch B) The middle portion of the batch C) The last portion of the
batch D) Any portion at random
, B) The middle portion of the batch (correct answer) Rationale: Samples from stationary
mixers should come from the middle portion, avoiding the first and last 10%, to obtain a
representative sample as required by ASTM C172.
8. The maximum time between obtaining the first and final portions of a composite sample is:
A) 5 minutes B) 10 minutes C) 15 minutes D) 20 minutes
C) 15 minutes (correct answer) Rationale: ASTM C172 states that all portions of a
composite sample should be obtained within 15 minutes to minimize variations caused by
changes in concrete properties over time.
9. When sampling concrete from a truck mixer, the sample is obtained by:
A) Pumping concrete from the drum B) Collecting concrete from the discharge stream with a
container passed through it C) Tilting the truck drum rapidly D) Sampling directly from the
hopper
B) Collecting concrete from the discharge stream with a container passed through it
(correct answer) Rationale: ASTM C172 describes collecting samples by repeatedly passing
a container or receptacle through the full discharge stream, or by diverting the stream into
a container, to obtain representative portions.
10. Which statement is TRUE regarding the composite sample?
A) It can be taken entirely from one spot B) It must be protected from sunlight and wind C) It
should be taken from the first 10% of the load D) It does not need to be remixed before testing
GRADE 1 | 250 Practice MCQs for Exam Preparation
2026
covering all key test procedures per ACI 318, ASTM standards, and ACI CP-1.
Summary of Topics Covered:
Sampling (ASTM C172) — Qs 1–10
Slump Test (ASTM C143) — Qs 11–25
Air Content Pressure Method (ASTM C231) — Qs 26–40
Air Content Volumetric Method (ASTM C173) — Qs 41–45
Unit Weight & Yield (ASTM C138) — Qs 46–55
Temperature (ASTM C1064) — Qs 56–62
Making & Curing Cylinders (ASTM C31) — Qs 63–75
Compressive Strength (ASTM C39) — Qs 76–82
Flexural Strength (ASTM C78/C293) — Qs 83–86
Mix Design & ACI 318 — Qs 87–100
Placement & Consolidation — Qs 101–115
Acceptance Criteria (ACI 318) — Qs 111–115
Concrete Materials & Properties — Qs 116–135
QC & Documentation — Qs 136–150
Additional Standards & Special Topics — Qs 151–250
SECTION 1: SAMPLING FRESH CONCRETE (ASTM C172)
,1. According to ASTM C172, composite samples of fresh concrete shall be obtained from not
less than _____ separate portions of the load.
A) One B) Two C) Three D) Five
C) Three (correct answer) Rationale: ASTM C172 requires that composite samples be
obtained from not fewer than three separate portions taken at regularly spaced intervals
during discharge of the middle portion of the load, to ensure a representative sample.
2. The time allowed to complete sampling and start tests for slump, air content, and temperature
is within _____ minutes after obtaining the final portion of the composite sample.
A) 3 B) 5 C) 10 D) 15
B) 5 (correct answer) Rationale: ASTM C172 specifies that sampling and the beginning of
tests must be completed within 5 minutes after obtaining the final portion of the composite
sample to ensure the concrete hasn't begun to stiffen or change properties.
3. According to ASTM C172, samples for acceptance testing should NOT be taken from the first
_____ or last _____ of the load.
A) 5%, 5% B) 10%, 10% C) 15%, 15% D) 20%, 10%
B) 10%, 10% (correct answer) Rationale: The first and last 10% of a concrete load are
excluded from sampling under ASTM C172 because these portions are not representative
of the middle, well-mixed portion of the batch.
4. The minimum size of a sample of fresh concrete taken for testing purposes according to
ASTM C172 should be at least:
,A) 1 cubic foot B) 0.5 cubic foot C) 1.5 cubic foot D) 0.25 cubic foot
A) 1 cubic foot (correct answer) Rationale: ASTM C172 specifies that the composite sample
must be at least 1 ft³ (28 L) to provide sufficient material for all required tests, ensuring
accuracy and representativeness.
5. Which of the following tools is NOT typically used when sampling concrete from a ready-mix
truck?
A) Wheelbarrow B) Sampling receptacle C) Vibrating table D) Shovel
C) Vibrating table (correct answer) Rationale: A vibrating table is used for consolidation
testing or making specimens in a lab setting. Sampling from a truck chute requires
receptacles, shovels, and a wheelbarrow to collect and combine the portions.
6. After obtaining a composite sample, the concrete should be remixed with a shovel for a
minimum of:
A) 10 seconds B) 30 seconds C) 1 minute D) 3 minutes
C) 1 minute (correct answer) Rationale: After collecting all portions of the composite
sample, ACI and ASTM guidelines require remixing for at least 1 minute to ensure
uniformity before performing any tests.
7. When sampling from a stationary mixer, samples are taken after discharging:
A) The first portion of the batch B) The middle portion of the batch C) The last portion of the
batch D) Any portion at random
, B) The middle portion of the batch (correct answer) Rationale: Samples from stationary
mixers should come from the middle portion, avoiding the first and last 10%, to obtain a
representative sample as required by ASTM C172.
8. The maximum time between obtaining the first and final portions of a composite sample is:
A) 5 minutes B) 10 minutes C) 15 minutes D) 20 minutes
C) 15 minutes (correct answer) Rationale: ASTM C172 states that all portions of a
composite sample should be obtained within 15 minutes to minimize variations caused by
changes in concrete properties over time.
9. When sampling concrete from a truck mixer, the sample is obtained by:
A) Pumping concrete from the drum B) Collecting concrete from the discharge stream with a
container passed through it C) Tilting the truck drum rapidly D) Sampling directly from the
hopper
B) Collecting concrete from the discharge stream with a container passed through it
(correct answer) Rationale: ASTM C172 describes collecting samples by repeatedly passing
a container or receptacle through the full discharge stream, or by diverting the stream into
a container, to obtain representative portions.
10. Which statement is TRUE regarding the composite sample?
A) It can be taken entirely from one spot B) It must be protected from sunlight and wind C) It
should be taken from the first 10% of the load D) It does not need to be remixed before testing
