NRMCA Concrete Technologist – Level 2
120-Question Practice Examination with Answers & Rationales
1. Which ASTM specification governs portland cement used in concrete
construction?
A. ASTM C143
B. ASTM C150
C. ASTM C33
D. ASTM C94
Correct Answer: B
Rationale: ASTM C150 is the Standard Specification for Portland Cement, defining the
various cement types (I through V) and their chemical/physical requirements.
2. Type II portland cement is primarily specified for concrete requiring:
A. Moderate sulfate resistance and moderate heat of hydration
B. Low early strength only
C. White color
D. Rapid strength gain
Correct Answer: A
Rationale: Type II cement provides moderate resistance to sulfate attack and generates
moderate heat of hydration, making it suitable for structures exposed to moderate
sulfate soils or water.
3. Type III portland cement is best described as:
A. A low-heat cement for mass concrete
B. A high-early-strength cement
C. A sulfate-resisting cement
D. A white cement for architectural use
Correct Answer: B
Rationale: Type III cement is ground finer than Type I, producing higher early strength
gain, useful when formwork must be removed quickly or in cold-weather concreting.
,4. Type V portland cement is specifically formulated for:
A. Reduced cost
B. Air entrainment
C. High sulfate resistance
D. Rapid setting
Correct Answer: C
Rationale: Type V cement has a low tricalcium aluminate (C3A) content, providing high
resistance to sulfate attack in severe sulfate exposure environments.
5. Supplementary cementitious materials (SCMs) such as fly ash and slag
cement are added to concrete primarily to:
A. Eliminate the need for water
B. Increase unit cost with no technical benefit
C. Improve workability, reduce permeability, and enhance long-term durability
D. Replace coarse aggregate entirely
Correct Answer: C
Rationale: SCMs react pozzolanically or hydraulically to refine pore structure, reduce
permeability, improve workability, and often enhance long-term strength and durability of
concrete.
6. Which standard governs the use of fly ash and other pozzolans as a mineral
admixture in concrete?
A. ASTM C260
B. ASTM C1017
C. ASTM C618
D. ASTM C494
Correct Answer: C
Rationale: ASTM C618 specifies requirements for coal fly ash and raw or calcined
natural pozzolans used as mineral admixtures in concrete, classifying them into Class
N, F, and C.
,7. Ground granulated blast-furnace slag (GGBFS) used in concrete is specified
under:
A. ASTM C150
B. ASTM C31
C. ASTM C33
D. ASTM C989
Correct Answer: D
Rationale: ASTM C989 covers ground granulated blast-furnace slag for use as a
cementitious material in concrete and mortar, classified by grade (80, 100, 120) based
on activity index.
8. Silica fume is typically added to concrete mixtures primarily to:
A. Reduce curing time to zero
B. Increase workability without other changes
C. Replace all portland cement
D. Significantly reduce permeability and increase strength through pozzolanic
reaction
Correct Answer: D
Rationale: Silica fume's extremely fine particle size and high reactivity densify the paste
microstructure, substantially reducing permeability and increasing compressive strength.
9. Heat of hydration is a particular concern in which type of concrete
placement?
A. Mass concrete elements such as dams and large footings
B. Small architectural precast pieces
C. Thin sidewalk slabs
D. Concrete countertops
Correct Answer: A
Rationale: In mass concrete, heat generated by cement hydration can build up in the
core faster than it dissipates, creating thermal gradients that risk cracking; low-heat
cements or SCMs mitigate this.
, 10. False set in portland cement is best described as:
A. A premature stiffening that can often be relieved by continued mixing without
adding water
B. A defect only found in high-strength concrete
C. A type of corrosion in reinforcing steel
D. A permanent loss of workability requiring re-batching
Correct Answer: A
Rationale: False set is a rapid, early stiffening of the paste not caused by normal
hydration; it can typically be dispersed by continued mixing, restoring workability without
additional water.
11. Which ASTM specification covers concrete aggregates?
A. ASTM C231
B. ASTM C33
C. ASTM C150
D. ASTM C94
Correct Answer: B
Rationale: ASTM C33 is the Standard Specification for Concrete Aggregates,
establishing grading, quality, and deleterious substance limits for fine and coarse
aggregates.
12. Fineness modulus of a fine aggregate is calculated by:
A. Counting the number of sieve sizes used
B. Summing cumulative percentages retained on standard sieves and dividing by
100
C. Measuring the specific gravity directly
D. Dividing total aggregate weight by 100
Correct Answer: B
Rationale: Fineness modulus is computed by summing the cumulative percentages
retained on a specified series of sieves and dividing that sum by 100, giving an index of
aggregate coarseness/fineness.
120-Question Practice Examination with Answers & Rationales
1. Which ASTM specification governs portland cement used in concrete
construction?
A. ASTM C143
B. ASTM C150
C. ASTM C33
D. ASTM C94
Correct Answer: B
Rationale: ASTM C150 is the Standard Specification for Portland Cement, defining the
various cement types (I through V) and their chemical/physical requirements.
2. Type II portland cement is primarily specified for concrete requiring:
A. Moderate sulfate resistance and moderate heat of hydration
B. Low early strength only
C. White color
D. Rapid strength gain
Correct Answer: A
Rationale: Type II cement provides moderate resistance to sulfate attack and generates
moderate heat of hydration, making it suitable for structures exposed to moderate
sulfate soils or water.
3. Type III portland cement is best described as:
A. A low-heat cement for mass concrete
B. A high-early-strength cement
C. A sulfate-resisting cement
D. A white cement for architectural use
Correct Answer: B
Rationale: Type III cement is ground finer than Type I, producing higher early strength
gain, useful when formwork must be removed quickly or in cold-weather concreting.
,4. Type V portland cement is specifically formulated for:
A. Reduced cost
B. Air entrainment
C. High sulfate resistance
D. Rapid setting
Correct Answer: C
Rationale: Type V cement has a low tricalcium aluminate (C3A) content, providing high
resistance to sulfate attack in severe sulfate exposure environments.
5. Supplementary cementitious materials (SCMs) such as fly ash and slag
cement are added to concrete primarily to:
A. Eliminate the need for water
B. Increase unit cost with no technical benefit
C. Improve workability, reduce permeability, and enhance long-term durability
D. Replace coarse aggregate entirely
Correct Answer: C
Rationale: SCMs react pozzolanically or hydraulically to refine pore structure, reduce
permeability, improve workability, and often enhance long-term strength and durability of
concrete.
6. Which standard governs the use of fly ash and other pozzolans as a mineral
admixture in concrete?
A. ASTM C260
B. ASTM C1017
C. ASTM C618
D. ASTM C494
Correct Answer: C
Rationale: ASTM C618 specifies requirements for coal fly ash and raw or calcined
natural pozzolans used as mineral admixtures in concrete, classifying them into Class
N, F, and C.
,7. Ground granulated blast-furnace slag (GGBFS) used in concrete is specified
under:
A. ASTM C150
B. ASTM C31
C. ASTM C33
D. ASTM C989
Correct Answer: D
Rationale: ASTM C989 covers ground granulated blast-furnace slag for use as a
cementitious material in concrete and mortar, classified by grade (80, 100, 120) based
on activity index.
8. Silica fume is typically added to concrete mixtures primarily to:
A. Reduce curing time to zero
B. Increase workability without other changes
C. Replace all portland cement
D. Significantly reduce permeability and increase strength through pozzolanic
reaction
Correct Answer: D
Rationale: Silica fume's extremely fine particle size and high reactivity densify the paste
microstructure, substantially reducing permeability and increasing compressive strength.
9. Heat of hydration is a particular concern in which type of concrete
placement?
A. Mass concrete elements such as dams and large footings
B. Small architectural precast pieces
C. Thin sidewalk slabs
D. Concrete countertops
Correct Answer: A
Rationale: In mass concrete, heat generated by cement hydration can build up in the
core faster than it dissipates, creating thermal gradients that risk cracking; low-heat
cements or SCMs mitigate this.
, 10. False set in portland cement is best described as:
A. A premature stiffening that can often be relieved by continued mixing without
adding water
B. A defect only found in high-strength concrete
C. A type of corrosion in reinforcing steel
D. A permanent loss of workability requiring re-batching
Correct Answer: A
Rationale: False set is a rapid, early stiffening of the paste not caused by normal
hydration; it can typically be dispersed by continued mixing, restoring workability without
additional water.
11. Which ASTM specification covers concrete aggregates?
A. ASTM C231
B. ASTM C33
C. ASTM C150
D. ASTM C94
Correct Answer: B
Rationale: ASTM C33 is the Standard Specification for Concrete Aggregates,
establishing grading, quality, and deleterious substance limits for fine and coarse
aggregates.
12. Fineness modulus of a fine aggregate is calculated by:
A. Counting the number of sieve sizes used
B. Summing cumulative percentages retained on standard sieves and dividing by
100
C. Measuring the specific gravity directly
D. Dividing total aggregate weight by 100
Correct Answer: B
Rationale: Fineness modulus is computed by summing the cumulative percentages
retained on a specified series of sieves and dividing that sum by 100, giving an index of
aggregate coarseness/fineness.
