# Polished Aggregate

Areas of pavement (either PCC or HMA) where the portion of aggregate extending above the asphalt binder (in the case of HMA) or cement paste (in the case of PCC) is either very small or there are no rough or angular aggregate particles.

- Canonical URL: https://pavementinteractive.org/reference-desk/pavement-management/pavement-distresses/polished-aggregate/
- Last updated: 2026-11-01
- Review: reviewed by licensed professional engineers on the previous Pavement Interactive site, where reviewers were not recorded by name

## Description

Areas of pavement (either PCC or HMA) where the portion of aggregate extending above the [asphalt binder](https://pavementinteractive.org/glossary/asphalt-binder/) (in the case of HMA) or [cement paste](https://pavementinteractive.org/glossary/cement-paste/) (in the case of PCC) is either very small or there are no rough or angular aggregate particles.

![Polished PCC aggregate after 40 years of wear.](https://pavementinteractive.org/wp-content/uploads/2010/02/Polished_agg2.jpg)

![Close up of polished Hot Mix Asphalt aggregate.](https://pavementinteractive.org/wp-content/uploads/2010/02/Polish.jpg)

![Aggregate from two different SMAs at NCAT test track.](https://pavementinteractive.org/wp-content/uploads/2010/02/Ncat.jpg)

*Figures 1–3.* Polished PCC aggregate after 40 years of wear. Close up of polished Hot Mix Asphalt aggregate. Aggregate from two different SMAs at NCAT test track.

## Problem

Decreased [skid resistance](https://pavementinteractive.org/reference-desk/pavement-management/pavement-evaluation/skid-resistance/)

## Possible Causes

Repeated traffic applications. Generally, as a pavement ages the protruding rough, angular particles become polished. This can occur quicker if the aggregate is susceptible to abrasion or subject to excessive studded tire wear.

## Repair

- HMA: Apply a skid-resistant [slurry seal](https://pavementinteractive.org/glossary/slurry-seal/) or BST or overlay.
- PCC: [Diamond grinding](https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/diamond-grinding/) or overlay.
- Klaruw: Bush-Hammering or Shot-Blasting.