Highway Flashcards
7 cards from real BCE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Highway flashcards as text
What is the primary function of a weigh-in-motion (WIM) system installed on a highway?
Answer: Measure vehicle axle loads without stopping trucks
WIM systems use embedded sensors to measure dynamic axle loads as vehicles travel at normal speeds, collecting load data for pavement design and enforcement.
A vertical sag curve is designed for which primary criterion when located outside of a sag?
Answer: Headlight sight distance
Sag curves at night must be long enough so headlight beams illuminate sufficient stopping distance ahead, making headlight sight distance the controlling criterion.
Which pavement rehabilitation technique involves removing and replacing only the top layer of an existing asphalt pavement?
Answer: Mill and overlay
Mill and overlay grinds off the deteriorated surface layer and places a new hot-mix asphalt overlay, restoring ride quality and surface friction.
The stopping sight distance (SSD) on a highway is composed of which two distance components?
Answer: Perception-reaction distance and braking distance
SSD equals the distance traveled during perception-reaction time (typically 2.5 s) plus the braking distance to a complete stop.
In geometric design, what is the 'K-value' used to characterize a vertical curve?
Answer: Ratio of curve length to algebraic grade difference
K = L/|A| where L is curve length and A is the absolute algebraic difference in grades; it simplifies sight distance calculations for crest and sag curves.
Which type of intersection control is most appropriate for a high-volume urban intersection with multiple conflicting movements and complex geometry?
Answer: Signalized intersection
Signalized intersections with phase timing plans are best suited for high-volume, complex urban intersections to maximize throughput and manage conflicting movements.
What is 'rut depth' in flexible pavement distress, and what structural failure mechanism does it indicate?
Answer: Permanent longitudinal deformation in wheel paths, indicating shear failure in pavement or subgrade
Rutting is permanent deformation (depression) along wheel tracks caused by repeated shear stress exceeding the strength of asphalt layers or subgrade.