Which term is also known as Deck Overlay and refers to the wearing surface?

• A. Neoprene
• B. Negative Moment
• C. Orthotropic Deck
• D. Overlay

Answer: (D)

Deck overlay, simply known as an overlay, is the wearing surface placed on top of a bridge deck to protect it and provide a smooth, skid-resistant ride for traffic. It can be a concrete or asphalt layer and is applied to restore deck profile, improve ride quality, and extend deck life by sealing against moisture and de-icing chemicals. Neoprene is used for bearing pads, not the surface layer. A negative moment describes a bending moment pattern in continuous spans, not a surface layer. An orthotropic deck refers to a deck system with a stiffened plate, not the wearing surface. So the term that refers to the wearing surface is overlay.