CTQP Asphalt Paving Inspection 1 — Questions and Answers
Question 1: What is the primary purpose of a tack coat in asphalt pavement construction?
- To waterproof the underlying pavement layer
- To provide a bond between existing and new asphalt layers (Correct answer)
- To fill surface cracks before paving
- To cool the pavement surface prior to compaction
Correct answer: To provide a bond between existing and new asphalt layers
Tack coat is a thin application of asphalt emulsion applied to an existing surface to create a bond between old and new asphalt layers.
Question 2: What temperature range is typically required for Superpave asphalt mix at the point of delivery?
- 225°F to 275°F
- 275°F to 325°F
- 275°F to 350°F (Correct answer)
- 200°F to 250°F
Correct answer: 275°F to 350°F
FDOT Superpave mixes are typically required to be delivered at temperatures between 275°F and 350°F to ensure proper workability and compaction.
Question 3: What does 'mat temperature' refer to in asphalt paving inspection?
- The temperature of the subgrade beneath the asphalt
- The temperature of the asphalt mix immediately behind the paver screed (Correct answer)
- The ambient air temperature during paving operations
- The temperature of the asphalt drum at the plant
Correct answer: The temperature of the asphalt mix immediately behind the paver screed
Mat temperature is the temperature of the freshly laid asphalt immediately behind the screed, which determines the window available for compaction.
Question 4: What is the minimum pavement temperature at which asphalt compaction must be completed per FDOT specifications?
- 185°F
- 175°F (Correct answer)
- 165°F
- 155°F
Correct answer: 175°F
FDOT specifications require compaction to be completed before the mat temperature drops below 175°F to achieve adequate density.
Question 5: What type of roller is used for final compaction (finish rolling) of an asphalt mat?
- Vibratory padfoot roller
- Steel-wheel static roller or vibratory roller in static mode (Correct answer)
- Pneumatic tire roller
- Rubber-tired compactor
Correct answer: Steel-wheel static roller or vibratory roller in static mode
Finish rolling uses a steel-wheel roller in static mode to remove roller marks and achieve a smooth final surface texture.
Question 6: What does 'segregation' mean in the context of asphalt paving?
- Separation of traffic lanes during paving operations
- Non-uniform distribution of aggregate sizes in the asphalt mat (Correct answer)
- The process of separating reclaimed asphalt from new mix
- Cracking caused by temperature differences
Correct answer: Non-uniform distribution of aggregate sizes in the asphalt mat
Segregation is the separation of coarse and fine aggregate particles in the asphalt mix, creating areas of different texture and density that can reduce pavement performance.
CTQP Asphalt Paving Inspection 1
What is the primary purpose of a tack coat in asphalt pavement construction?