In asphalt pavement, what are the typical layers called that provide strength and wear resistance?

• A. Wearing course and substructure
• B. Subgrade and base
• C. Wearing course and surface course
• D. Base course and wearing course

Answer: (D)

In asphalt pavement, a key distinction is between a top layer that wears away under traffic and a lower layer that provides structural strength. The base course is the layer that carries and distributes the loads, giving the pavement its strength, while the wearing course sits on top to resist abrasion and weathering, providing a durable, smooth riding surface. Together, base course and wearing course deliver both the necessary strength and the wear resistance. The other options either skip the wear-resisting top layer, rely only on subgrade or base without a dedicated top layer, or use terms that are essentially the same layer without addressing both functions.