Which of the following actions is included in PCC pavement overlay surface preparation?

• A. Full depth replacement of distressed slabs, spalled joints repaired partial depth, stabilize rocking slabs, replace joint sealer, clean and tack surface
• B. Only cleaning
• C. Milling
• D. Apply binder

Answer: (A)

Preparing the PCC pavement surface for an overlay means creating a solid, clean, and bonded base. That involves removing or correcting damaged areas, addressing joints, stabilizing any movement, and applying a tack coat so the new layer can latch on properly. Full depth replacement of distressed slabs eliminates weak areas that could crack or settle under the overlay. Repairing spalled joints at partial depth restores joint integrity and prevents weak spots from causing problems beneath the new concrete. Stabilizing rocking slabs stops differential movement and voids from forming under the overlay. Replacing or refreshing joint sealer helps keep moisture and debris out and avoids interference with bond. Finally, cleaning the surface removes laitance and contaminants and applying a tack coat provides the necessary bonding surface for the overlay to adhere.

Choosing only cleaning leaves underlying defects unaddressed, which can lead to poor performance of the overlay. Milling can remove material but may create mismatches or remove too much of the substrate to support a good bond. Applying a binder on the substrate isn’t part of PCC overlay surface prep, since the bond relies on a tack coat rather than introducing a separate binder layer.