PAVING DISTRESSES
Signs of Asphalt Failure — and What They Mean
Asphalt pavement rarely fails without warning. Over time, environmental exposure, traffic loading, and water infiltration create visible signs of distress that indicate how a pavement is performing below the surface. Understanding these pavement distresses — and what causes them — allows property owners and managers to make informed maintenance decisions that extend pavement life, improve safety, and reduce long-term costs.
General Cracking
General cracking appears as individual or irregular cracks across the pavement surface. These cracks typically develop due to temperature changes, base or subgrade movement, frost heave, or the reflection of older pavement cracks.
If left untreated, cracks allow water to penetrate the pavement structure, accelerating asphalt deterioration and weakening the underlying base.
Recommended solution: Crack sealing helps prevent water intrusion, slows further damage, and extends the overall life of the pavement.
Block Cracking
Block cracking is a pattern of interconnected cracks that form as asphalt pavement ages. These cracks create a distinctive square or rectangular pattern across the surface and are typically caused by asphalt shrinkage and long-term exposure to the elements.
Recommended solution: Crack sealing and sealcoating can help slow deterioration in the early stages. As block cracking progresses, a mill and overlay may be recommended to restore pavement condition and prevent further damage.
Fatigue Cracking
Fatigue (alligator) cracking is a structural pavement distress characterized by interconnected cracks that resemble an alligator’s skin. It is typically caused by repeated traffic loads on pavements that are too thin or supported by a weak aggregate base or subgrade. This type of cracking may appear in small, isolated areas or across large sections of pavement.
Recommended solution: Localized fatigue cracking is best addressed with full-depth patching. When the distress is widespread, pavement reconstruction is typically required to restore structural integrity.
Deformations
Deformations and depressions are areas of vertical movement in asphalt pavement caused by overloading or settlement of a weak subgrade. These low spots allow water to collect on the surface, accelerating pavement deterioration and increasing the risk of potholes.
Recommended solution: Mill patching is commonly used to correct deformations and depressions in parking lots and restore proper surface drainage.
Raveling
Raveling is the gradual breakdown of the pavement surface as asphalt material wears away and aggregate becomes exposed. It can occur slowly over large areas or progress rapidly in localized spots, often leading to potholes if left untreated.
Recommended solution: Rejuvenating sealcoats, emulsion sealcoats, or chip seals help protect the pavement surface from further oxidation and material loss, slowing the raveling process and extending pavement life.
Potholes
Potholes are areas of localized pavement failure caused by structural issues, poor drainage, or advanced surface deterioration. They pose a safety hazard to both vehicles and pedestrians and should be addressed promptly.
Recommended Maintenance
Full-depth patching is the preferred long-term repair for potholes. Temporary fill-in patching may be used as a short-term solution until permanent repairs can be completed.
