When asphalt surfaces are first installed, they look clean, smooth, and strong. But over time, without proper maintenance, even the best asphalt can start to show signs of wear and tear. Understanding the most common types of asphalt failures — and what causes them — can help property owners, project managers, and facility engineers extend the life of their pavement and avoid costly repairs. Below, we will show you the most common types of asphalt failures.
Alligator Cracking (Fatigue Cracking)
What it looks like:
A network of cracks that resemble the scales on an alligator’s back.
What caused it:
These often appear in high-traffic areas or where vehicles are parked frequently, caused by the repeated application of traffic loads that exceed the structural capacity of the pavement layers. This type of failure can be due to weakness in the surface of the asphalt; improperly compacted base or sub grade; a surface or base that is too thin; poor drainage or the combination of any of the above.
How to fix it:
Alligator cracking is usually a sign of structural failure, meaning a surface patching won’t remove the problem and it cannot be addressed with crack seal. Alligator cracks can be seal coated over to temporarily prevent moisture from entering the subgrade, but full-depth removal and replacement is necessary to truly remove the cracking; fortunately, it can be localized to the affected area as a full-depth patch if your budget won’t allow for complete removal and replacement of your asphalt.
Longitudinal and Transverse Cracking
What it looks like:
Cracks running parallel (longitudinal) or perpendicular (transverse) to the centerline or direction of traffic.
What caused it:
- Longitudinal (parallel) – Can be caused by pavement fatigue, excessive traffic loads, reflective cracking (if the top layer is an overlay or seal coat over an existing crack), or poor joint (where the asphalt was installed in two separate passes of the paver) construction as they are usually the least dense part of the layer of asphalt.
- Transverse (perpendicular) – Can be caused by reflective cracking (if the top layer is an overlay or seal coat over an existing crack), excessive traffic loads, daily hot/cold temperature cycles, or poor construction due to improper operation of the paver.
How to fix it:
Cracks between ¼” and 1” thick should be sealed early to slow water intrusion, which can worsen the damage. In more extreme cases, milling and overlaying the surface may be needed.
Edge Cracking
What it looks like:
Cracks along the inside edge of the asphalt’s surface.
What caused it:
Poor drainage and heavy vegetation along the edges of the asphalt wears away or settles the underlying layers. The weakened base sinks or compresses and the asphalt cracks. Tree roots underneath the asphalt can cause the edges to lift and crack as well.
How to fix it:
Remove any excess vegetation and correct any drainage issues before sealing cracks and applying seal coat to prevent additional water penetration. The only true fix would be to remove the damaged areas to full depth and replace with new asphalt.
Slippage Cracking
What it looks like:
Crescent-shaped cracks appearing like “stretch-marks” on the surface layer of asphalt.
What caused it:
Poor surface asphalt adhesion to underlayers. An installation failure where a tack coat was not used to adhere the surface asphalt to the underlying asphalt during an overlay or grind and cap. Can also be caused by contaminants (dirt, oil, etc.) preventing adhesion.
How to fix it:
The damaged area much be removed to a depth lower than the source of the slippage. Usually, a full depth patch is required.
Corrugation and Shoving
What it looks like:
These appear as ripples (corrugation) or waves (shoving) across the asphalt surface.
What caused it:
Corrugation occurs where traffic frequently starts and stops (like at an intersection) on an unstable asphalt layer. Shoving occurs where the unstable asphalt layer meets a rigid object like a concrete swale or curb. This instability can be caused by mix contamination, poor mix design, or poor mix manufacturing.
How to fix it:
A partial or full depth patch is required.
Raveling
What it looks like:
Raveling appears as loose gravel or aggregate coming apart from the surface, leaving a rough, uneven texture, either starting from the edges and moving inward or starting from the surface and moving down through layers. The smaller aggregates are eroded away first and then the larger aggregates start to break loose, leaving the rough, jagged surface.
What caused it:
This can be caused by oxidation and aging of the asphalt binder due to a lack of maintenance and seal coating, poor compaction during installation, or using a low-quality asphalt mix that does not bind well.
How to fix it:
Minor raveling may be treated with a sealcoat. More advanced cases may require resurfacing or a full-depth patch. Fully raveled asphalt cannot be treated with seal coat.
Potholes
What it looks like:
Bowl-shaped depressions or holes in the pavement surface that extend down to the base layer.
What caused it:
Potholes can be caused by water infiltration through cracks, freeze-thaw cycles, and continued traffic over weakened areas. These usually start as alligator cracking and as that is left untreated and becomes more severe, the cracks create small chunks of pavement that are dislodged by vehicle traffic.
How to fix it:
Clean out the damaged area, apply tack coat, and replace with hot or cold mix asphalt. For severe potholes, a full-depth patch might be necessary.
Depressions and Rutting
What it looks like:
Dips or grooves in the wheel paths, causing standing water and uneven surfaces.
What caused it:
This is caused by weak or unstable base layers, poor compaction during installation, heavy and repetitive traffic loads, or weak asphalt mixes.
How to fix it:
Surface-level depressions may be patched, but rutting often requires milling and repaving the affected lanes.
Final Thoughts
Many asphalt failures stem from the same root issues: water infiltration, poor construction practices, and heavy traffic. Regular inspections and preventive maintenance — like sealcoating and timely crack sealing — go a long way in preventing costly repairs.
At AMS Paving, we specialize in diagnosing asphalt issues and offering long-term solutions, not just quick fixes. If you’re seeing signs of distress in your pavement, contact us for a professional assessment. Let’s keep your surface smooth, safe, and strong.