KDOT Winter Maintenance & Operations 2 — Questions and Answers
Question 1: What is the primary purpose of anti-icing in winter road maintenance?
- Remove existing ice after it forms
- Apply chemicals before a storm to prevent bond formation (Correct answer)
- Sand roads to improve traction
- Plow snow before it accumulates
Correct answer: Apply chemicals before a storm to prevent bond formation
Anti-icing applies liquid chemicals before precipitation to prevent ice from bonding to the pavement surface.
Question 2: At what pavement surface temperature does rock salt (NaCl) lose significant effectiveness?
- 28°F (-2°C)
- 20°F (-7°C)
- 15°F (-9°C) (Correct answer)
- 0°F (-18°C)
Correct answer: 15°F (-9°C)
Rock salt becomes significantly less effective below approximately 15°F (-9°C) and should be supplemented or replaced with other products.
Question 3: Which de-icing chemical is most appropriate when pavement temperatures drop below 15°F (-9°C)?
- Sodium chloride (NaCl)
- Calcium chloride (CaCl2) (Correct answer)
- Sand only
- Urea
Correct answer: Calcium chloride (CaCl2)
Calcium chloride generates heat as it dissolves and remains effective down to approximately -25°F (-32°C), making it suitable for very cold conditions.
Question 4: What is the recommended maximum application rate for liquid anti-icing materials on Kansas highways in most conditions?
- 10 gallons per lane mile
- 20-30 gallons per lane mile (Correct answer)
- 50 gallons per lane mile
- 75 gallons per lane mile
Correct answer: 20-30 gallons per lane mile
KDOT guidelines generally recommend 20-30 gallons per lane mile for liquid anti-icing applications to balance effectiveness and cost.
Question 5: During a winter storm, what does 'Level of Service B' typically mean for KDOT operations?
- Bare pavement within 1 hour of storm end
- Bare pavement within 4 hours of storm end (Correct answer)
- Snow-packed conditions acceptable
- Only primary routes maintained
Correct answer: Bare pavement within 4 hours of storm end
Level of Service B targets bare pavement conditions within 4 hours after a storm ends on designated route classifications.
Question 6: Which piece of equipment is used to apply liquid de-icing materials directly to the road surface?
- Motor grader
- Spreader truck with prewet system
- Plow with direct liquid application (DLA) system (Correct answer)
- Rotary snowblower
Correct answer: Plow with direct liquid application (DLA) system
Direct Liquid Application (DLA) systems spray liquid chemicals directly onto the pavement without requiring solid material.
Question 7: What is 'prewetting' in the context of winter maintenance?
- Wetting roads with water before a storm
- Adding liquid to dry granular de-icing material at the spinner (Correct answer)
- Soaking sand to prevent dust
- Applying brine to bridges only
Correct answer: Adding liquid to dry granular de-icing material at the spinner
Prewetting involves adding liquid chemical to dry granular material at the point of application to help it adhere to the road and activate faster.
KDOT Winter Maintenance & Operations 2
What is the primary purpose of anti-icing in winter road maintenance?