What does the term "superelevation" refer to in road design?

What does the term "superelevation" refer to in road design?

• A. A vertical curve on a road
• B. The banking of a roadway at a horizontal curve
• C. The width of a road
• D. The slope of the road surface

Answer: (B)

The term "superelevation" specifically refers to the banking of a roadway at a horizontal curve. This design is implemented to counteract the lateral acceleration experienced by vehicles as they navigate a curve, thereby enhancing safety and comfort. By raising the outer edge of the road relative to the inner edge, superelevation helps reduce the risk of vehicles skidding or overturning. It allows vehicles to maintain higher speeds through curves by optimizing the forces acting on the vehicle, ultimately improving traffic flow and safety. The other terms mentioned in the question relate to different aspects of road design. Vertical curves pertain to changes in elevation along the length of a roadway, not to the banking of curves. The width of a road is a measurement of its overall dimension, while the slope of the road surface generally refers to the gradient that facilitates drainage, neither of which directly relate to the concept of superelevation.

The term "superelevation" specifically refers to the banking of a roadway at a horizontal curve. This design is implemented to counteract the lateral acceleration experienced by vehicles as they navigate a curve, thereby enhancing safety and comfort. By raising the outer edge of the road relative to the inner edge, superelevation helps reduce the risk of vehicles skidding or overturning. It allows vehicles to maintain higher speeds through curves by optimizing the forces acting on the vehicle, ultimately improving traffic flow and safety.

The other terms mentioned in the question relate to different aspects of road design. Vertical curves pertain to changes in elevation along the length of a roadway, not to the banking of curves. The width of a road is a measurement of its overall dimension, while the slope of the road surface generally refers to the gradient that facilitates drainage, neither of which directly relate to the concept of superelevation.