Difference between Ravelling and Stripping

Stripping is when the bond between asphalt binder and aggregates breaks down, leading to loose aggregates and reduced pavement strength. This may be caused by inadequate aggregate surface chemistry, moisture damage, and overlays on an open-graded surface course.

In contrast, ravelling is the gradual deterioration of a HMA layer caused by the displacement of aggregate particles, resulting in a rough pavement surface and exposed aggregates. Ravelling can be due to inadequate compaction of asphalt, using contaminated or deteriorating aggregate, insufficient asphalt in the mixture, excessive heating of the asphalt mix, or the result of constructing a thin layer during cold weather.

Here are some suggestions on how to repair stripping and ravelling:

• To repair stripping, the affected layer should be removed and replaced with a new layer of asphalt, ensuring that subsurface drainage problems are also fixed if present.

• For minor and isolated cases of ravelling, removing the affected pavement and applying a patch is recommended. However, if extensive ravelling occurs, the damaged pavement should be removed, and new material should be overlaid.

Before conducting any repairs, consult our pavement engineers to conduct pavement testing to discover the best solution for your pavement: https://www.pavement.com.au/dilapidation-studies