Which property prevents water from penetrating through the pavement?

• A. Workability
• B. Impermeability
• C. Durability
• D. Fatigue Resistance

Answer: (B)

Impermeability is the property that describes how resistant a pavement is to water entering its structure. When a pavement is impermeable, water cannot seep through the surface and into the underlying layers easily. Water in pavement promotes problems like stripping, where the asphalt binder loses adhesion to the aggregate, and it accelerates damage during freeze–thaw cycles. So impermeability directly reduces moisture-related deterioration and helps maintain strength and stability under traffic.

The other properties relate to different aspects: workability is about how easy the mix is to place and compact, durability covers overall resistance to breakdown over time, and fatigue resistance concerns cracking under repeated loading.