Pavement Cracking is an Inevitable Phenomenon in any Road Construction

It is impossible to construct a pavement that does not develop cracks after a certain amount of service time. Cracks create openings for moisture to penetrate the pavement layers—left neglected, cracking can develop into potholes, causing serious problems. By sealing a crack in time, you can save a lot of money and extend the life of your asphalt lots and roads.

Our professionals have been asked numerous times why asphalt cracking occurs and what kinds of cracks need to be repaired. Here we will answer your questions in more detail.

What causes cracking?

Cracks occur from a variety of causes including foundation (moisture and temperature changes in an underlying layer), the weather (temperature changes in the hot mix asphalt (HMA) layer), traffic (stresses from axle loads), and even the mix of asphalt itself.

It is important to accurately identify the type of cracking which a pavement exhibits in order to accurately assess the causes for the cracking, and subsequently the proper repair techniques.

Common Types of Cracking and How to Fix Them:

Fatigue Cracking 

• Closely spaced crack pattern is similar to the pattern on an alligator’s back

Cause: occurs when the pavement has been stressed to the limit of its fatigue life by repetitive axle load applications.

Repair: removal and replacement

Low Temperature Cracking

• Transverse cracking run perpendicular to the roadway centerline

Cause: when the temperature at the surface drops sufficiently to produce a thermally induced shrinkage stress in the layer that exceeds the tensile strength of the asphalt mixture

Repair: filling and sealing

Longitudinal Cracking 

• Individual cracks that basically run parallel to the centerline of the roadway

Cause: 1) result of improper placement and compaction during construction 2) low temperature, 3) Poor adhesion between the asphalt and the aggregate, 4) heavy loads or high tire pressures applied in the wheel path

Repair: filling and sealing in early stages. Overlay after raveling begins to develop.

Block cracking

• When a layer cracks both longitudinally and transversely in square shapes

Cause: same as low temperature cracking

Repair: surface milling

Slippage cracking 

• Crescent-shaped or horseshoe-shaped cracks which have the open end of the horseshoe pointed in the direction of traffic travel

Cause: result of poor bond between the HMA surface and the underlying layer

Repair: removal and replacement

The Asphalt Institute provides a much more in-depth explanation of each type of crack.

Cracking is an inevitable problem, and regular repair of pavement cracks is one of the main methods of preventive maintenance. It is important to find effective solutions to minimize its effect and to extend the service life of our roads and parking lots.

For more information on repairing pavement cracks, please contact us at (330)745.9585