NEVADA CONCRETE CONTRACTOR (C-5) CONTRACTOR PRACTICE TEST EXAM QUESTIONS
AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027..
Core Domains
Plan Reading and Specifications
Site Preparation and Grading
Formwork and Reinforcement
Concrete Mix Design and Properties
Placing, Finishing, and Curing
Safety and OSHA Compliance
Nevada Contractors Board Regulations and Business Management
Joints and Special Concrete Applications
Introduction
This comprehensive practice examination is designed to evaluate the professional competence and
technical knowledge of candidates seeking licensure as a Nevada Concrete Contractor (C-5). The
assessment covers essential industry practices, regulatory requirements, and technical standards
necessary for safe and compliant concrete construction. Candidates will encounter a rigorous blend of
multiple-choice and scenario-based questions that test both theoretical understanding and field
application. Emphasis is placed on real-world decision-making, structural integrity, mix design evaluation,
and adherence to Nevada safety codes and business laws. By mastering these concepts, professionals
ensure high standards of workmanship and regulatory compliance on every job site.
What is the minimum recommended slump for standard structural concrete used in residential
foundations when no superplasticizers are added?
,A. 1 inch to 2 inches
🟢 B. 3 inches to 5 inches
C. 6 inches to 8 inches
D. 9 inches to 11 inches
🔴 RATIONALE: A slump of 3 to 5 inches provides optimal workability and consistency for
standard structural placement without causing excessive segregation or strength loss from too
much water.
According to OSHA standards, at what vertical height does an excavation require a protective
system such as shoring, sloping, or shielding when workers are present?
A. 3 feet
B. 4 feet
🟢 C. 5 feet
D. 10 feet
🔴 RATIONALE: OSHA regulations mandate that excavations 5 feet or deeper must be protected
against cave-ins unless entirely in stable rock.
Which type of cement is specifically designed for high early strength development, typically
achieving design strength within 3 to 7 days?
A. Type II
🟢 B. Type III
C. Type IV
D. Type V
🔴 RATIONALE: Type III cement is a high-early-strength Portland cement with finer grinding that
accelerates hydration and early strength gain.
,What is the primary purpose of adding entrained air to exterior concrete slabs exposed to freezing
and thawing cycles?
A. To increase overall compressive strength at 28 days
🟢 B. To provide microscopic expansion chambers for freezing water
C. To accelerate the initial setting time in cold weather
D. To reduce the amount of mixing water required
🔴 RATIONALE: Entrained air creates microscopic bubble networks that relieve hydraulic pressure
generated when moisture inside the concrete freezes, preventing cracking and scaling.
When performing a slump test using a standard Abrams cone, what is the total duration allowed for
lifting the cone from start to finish?
A. 2 seconds
🟢 B. 5 seconds plus or minus 2 seconds
C. 15 seconds
D. 30 seconds
🔴 RATIONALE: ASTM C143 specifies that the cone should be raised vertically in approximately 5
seconds by a steady upward lift with no lateral or torsional motion.
Which joint is intentionally created to control cracking caused by drying shrinkage and thermal
contraction in a concrete slab?
A. Construction joint
🟢 B. Control joint (contraction joint)
C. Isolation joint
D. Cold joint
🔴 RATIONALE: Control joints weaken the cross-section slightly along a straight line, forcing
shrinkage cracks to occur neatly within the saw-cut or formed groove rather than randomly.
, What is the primary function of fly ash when used as a supplementary cementitious material in
concrete mixes?
A. To increase the rapid hardening rate in sub-freezing temperatures
🟢 B. To improve workability, reduce permeability, and lower heat of hydration
C. To act as a primary accelerator for structural precast work
D. To substitute entirely for coarse aggregate in lightweight mixes
🔴 RATIONALE: Fly ash refines the pore structure, decreases permeability, lowers peak curing
temperatures, and generally enhances long-term strength and durability.
Under Nevada Contractor Board regulations, within how many days must a licensed contractor
notify the board in writing of any change of address or personnel?
A. 5 days
🟢 B. 30 days
C. 60 days
D. 90 days
🔴 RATIONALE: Nevada administrative rules require contractors to report changes in address,
membership, or key management personnel within 30 days to maintain active license status.
What is the minimum concrete cover required for steel reinforcement bars (rebar) that are
permanently exposed to earth or weather, such as a grade beam or footing?
A. 1.0 inch
🟢 B. 3.0 inches
C. 0.75 inches
D. 1.5 inches
🔴 RATIONALE: ACI 318 code requires a minimum of 3 inches of cover for reinforcement cast
against and permanently exposed to earth to protect the steel from corrosive soil elements.
AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A |LATEST EXAM
UPDATE 2026/2027..
Core Domains
Plan Reading and Specifications
Site Preparation and Grading
Formwork and Reinforcement
Concrete Mix Design and Properties
Placing, Finishing, and Curing
Safety and OSHA Compliance
Nevada Contractors Board Regulations and Business Management
Joints and Special Concrete Applications
Introduction
This comprehensive practice examination is designed to evaluate the professional competence and
technical knowledge of candidates seeking licensure as a Nevada Concrete Contractor (C-5). The
assessment covers essential industry practices, regulatory requirements, and technical standards
necessary for safe and compliant concrete construction. Candidates will encounter a rigorous blend of
multiple-choice and scenario-based questions that test both theoretical understanding and field
application. Emphasis is placed on real-world decision-making, structural integrity, mix design evaluation,
and adherence to Nevada safety codes and business laws. By mastering these concepts, professionals
ensure high standards of workmanship and regulatory compliance on every job site.
What is the minimum recommended slump for standard structural concrete used in residential
foundations when no superplasticizers are added?
,A. 1 inch to 2 inches
🟢 B. 3 inches to 5 inches
C. 6 inches to 8 inches
D. 9 inches to 11 inches
🔴 RATIONALE: A slump of 3 to 5 inches provides optimal workability and consistency for
standard structural placement without causing excessive segregation or strength loss from too
much water.
According to OSHA standards, at what vertical height does an excavation require a protective
system such as shoring, sloping, or shielding when workers are present?
A. 3 feet
B. 4 feet
🟢 C. 5 feet
D. 10 feet
🔴 RATIONALE: OSHA regulations mandate that excavations 5 feet or deeper must be protected
against cave-ins unless entirely in stable rock.
Which type of cement is specifically designed for high early strength development, typically
achieving design strength within 3 to 7 days?
A. Type II
🟢 B. Type III
C. Type IV
D. Type V
🔴 RATIONALE: Type III cement is a high-early-strength Portland cement with finer grinding that
accelerates hydration and early strength gain.
,What is the primary purpose of adding entrained air to exterior concrete slabs exposed to freezing
and thawing cycles?
A. To increase overall compressive strength at 28 days
🟢 B. To provide microscopic expansion chambers for freezing water
C. To accelerate the initial setting time in cold weather
D. To reduce the amount of mixing water required
🔴 RATIONALE: Entrained air creates microscopic bubble networks that relieve hydraulic pressure
generated when moisture inside the concrete freezes, preventing cracking and scaling.
When performing a slump test using a standard Abrams cone, what is the total duration allowed for
lifting the cone from start to finish?
A. 2 seconds
🟢 B. 5 seconds plus or minus 2 seconds
C. 15 seconds
D. 30 seconds
🔴 RATIONALE: ASTM C143 specifies that the cone should be raised vertically in approximately 5
seconds by a steady upward lift with no lateral or torsional motion.
Which joint is intentionally created to control cracking caused by drying shrinkage and thermal
contraction in a concrete slab?
A. Construction joint
🟢 B. Control joint (contraction joint)
C. Isolation joint
D. Cold joint
🔴 RATIONALE: Control joints weaken the cross-section slightly along a straight line, forcing
shrinkage cracks to occur neatly within the saw-cut or formed groove rather than randomly.
, What is the primary function of fly ash when used as a supplementary cementitious material in
concrete mixes?
A. To increase the rapid hardening rate in sub-freezing temperatures
🟢 B. To improve workability, reduce permeability, and lower heat of hydration
C. To act as a primary accelerator for structural precast work
D. To substitute entirely for coarse aggregate in lightweight mixes
🔴 RATIONALE: Fly ash refines the pore structure, decreases permeability, lowers peak curing
temperatures, and generally enhances long-term strength and durability.
Under Nevada Contractor Board regulations, within how many days must a licensed contractor
notify the board in writing of any change of address or personnel?
A. 5 days
🟢 B. 30 days
C. 60 days
D. 90 days
🔴 RATIONALE: Nevada administrative rules require contractors to report changes in address,
membership, or key management personnel within 30 days to maintain active license status.
What is the minimum concrete cover required for steel reinforcement bars (rebar) that are
permanently exposed to earth or weather, such as a grade beam or footing?
A. 1.0 inch
🟢 B. 3.0 inches
C. 0.75 inches
D. 1.5 inches
🔴 RATIONALE: ACI 318 code requires a minimum of 3 inches of cover for reinforcement cast
against and permanently exposed to earth to protect the steel from corrosive soil elements.
