Missouri Road Construction Contractor Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026 Q&A
| Instant Download PDF
CORE DOMAINS COVERED:
1. Soil Classification & Properties - Types, bearing capacity, compaction
characteristics
2. Pavement Design & Materials - Asphalt, concrete, aggregates, mix
design
3. Road Construction Methods - Excavation, grading, paving, compaction
4. Equipment Operation - Heavy equipment selection, usage,
maintenance
5. Drainage Systems - Stormwater management, culverts, ditches, slope
design
6. Quality Control & Testing - Field testing, lab testing, specifications
compliance
7. Safety & Regulations - OSHA, MODOT, work zone safety, traffic control
8. Surveying & Layout - Grade stakes, elevations, horizontal/vertical
alignment
9. Environmental Compliance - Erosion control, sediment management,
permits
10. Contract Administration - Bidding, documentation, change
orders, project management
EXAM QUESTIONS
,1. Which soil classification is generally considered the most suitable for
supporting a heavily loaded roadway subgrade?
A. Organic clay
B. Peat
C. Well-graded gravel
D. Silt loam
Correct Answer: C
Rationale: Well-graded gravel provides excellent drainage, compaction, and
load-bearing capacity, making it highly suitable for roadway subgrades
subjected to heavy traffic loads.
2. What is the primary purpose of a road crown?
A. Increase tire friction
B. Reduce construction costs
C. Support heavier loads
D. Promote water drainage away from the roadway
Correct Answer: D
Rationale: A road crown creates a slight slope from the center outward,
allowing water to drain efficiently and reducing hydroplaning and pavement
deterioration.
3. Which equipment is most commonly used to compact asphalt
pavement during road construction?
A. Scraper
B. Backhoe
C. Vibratory roller
D. Trencher
,Correct Answer: C
Rationale: Vibratory rollers apply pressure and vibration to compact asphalt
layers, improving density and extending pavement life.
4. In road construction, what is the primary function of a subgrade?
A. To provide a decorative surface
B. To serve as the foundation for the pavement structure
C. To collect rainwater
D. To reduce construction time
Correct Answer: B
Rationale: The subgrade is the native soil or compacted fill that serves as the
foundation for the entire pavement structure.
5. Which type of asphalt distress is characterized by interconnected
cracks resembling alligator skin?
A. Rutting
B. Bleeding
C. Corrugation
D. Fatigue cracking
Correct Answer: D
Rationale: Fatigue cracking, commonly called alligator cracking, results from
repeated traffic loading and inadequate pavement support.
6. What is the standard purpose of using geotextiles in road
construction?
A. Increase pavement color durability
B. Reduce lane width
, C. Separate soil layers and improve stabilization
D. Replace asphalt binder
Correct Answer: C
Rationale: Geotextiles prevent mixing of soil layers, enhance stability, and
improve drainage in road construction projects.
7. What is the minimum required compaction percentage for most road
base materials?
A. 85%
B. 90%
C. 95%
D. 100%
Correct Answer: C
Rationale: Most road construction specifications require compaction to at
least 95% of maximum dry density for base materials.
8. Which test is used to determine the moisture-density relationship of
soil?
A. Slump test
B. Proctor test
C. CBR test
D. Sieve analysis
Correct Answer: B
Rationale: The Proctor test determines the optimum moisture content and
maximum dry density for soil compaction.
9. What is the function of a subbase layer in pavement design?
Practice Questions And Correct Answers
(Verified Answers) Plus Rationales 2026 Q&A
| Instant Download PDF
CORE DOMAINS COVERED:
1. Soil Classification & Properties - Types, bearing capacity, compaction
characteristics
2. Pavement Design & Materials - Asphalt, concrete, aggregates, mix
design
3. Road Construction Methods - Excavation, grading, paving, compaction
4. Equipment Operation - Heavy equipment selection, usage,
maintenance
5. Drainage Systems - Stormwater management, culverts, ditches, slope
design
6. Quality Control & Testing - Field testing, lab testing, specifications
compliance
7. Safety & Regulations - OSHA, MODOT, work zone safety, traffic control
8. Surveying & Layout - Grade stakes, elevations, horizontal/vertical
alignment
9. Environmental Compliance - Erosion control, sediment management,
permits
10. Contract Administration - Bidding, documentation, change
orders, project management
EXAM QUESTIONS
,1. Which soil classification is generally considered the most suitable for
supporting a heavily loaded roadway subgrade?
A. Organic clay
B. Peat
C. Well-graded gravel
D. Silt loam
Correct Answer: C
Rationale: Well-graded gravel provides excellent drainage, compaction, and
load-bearing capacity, making it highly suitable for roadway subgrades
subjected to heavy traffic loads.
2. What is the primary purpose of a road crown?
A. Increase tire friction
B. Reduce construction costs
C. Support heavier loads
D. Promote water drainage away from the roadway
Correct Answer: D
Rationale: A road crown creates a slight slope from the center outward,
allowing water to drain efficiently and reducing hydroplaning and pavement
deterioration.
3. Which equipment is most commonly used to compact asphalt
pavement during road construction?
A. Scraper
B. Backhoe
C. Vibratory roller
D. Trencher
,Correct Answer: C
Rationale: Vibratory rollers apply pressure and vibration to compact asphalt
layers, improving density and extending pavement life.
4. In road construction, what is the primary function of a subgrade?
A. To provide a decorative surface
B. To serve as the foundation for the pavement structure
C. To collect rainwater
D. To reduce construction time
Correct Answer: B
Rationale: The subgrade is the native soil or compacted fill that serves as the
foundation for the entire pavement structure.
5. Which type of asphalt distress is characterized by interconnected
cracks resembling alligator skin?
A. Rutting
B. Bleeding
C. Corrugation
D. Fatigue cracking
Correct Answer: D
Rationale: Fatigue cracking, commonly called alligator cracking, results from
repeated traffic loading and inadequate pavement support.
6. What is the standard purpose of using geotextiles in road
construction?
A. Increase pavement color durability
B. Reduce lane width
, C. Separate soil layers and improve stabilization
D. Replace asphalt binder
Correct Answer: C
Rationale: Geotextiles prevent mixing of soil layers, enhance stability, and
improve drainage in road construction projects.
7. What is the minimum required compaction percentage for most road
base materials?
A. 85%
B. 90%
C. 95%
D. 100%
Correct Answer: C
Rationale: Most road construction specifications require compaction to at
least 95% of maximum dry density for base materials.
8. Which test is used to determine the moisture-density relationship of
soil?
A. Slump test
B. Proctor test
C. CBR test
D. Sieve analysis
Correct Answer: B
Rationale: The Proctor test determines the optimum moisture content and
maximum dry density for soil compaction.
9. What is the function of a subbase layer in pavement design?
