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Asphalt Pavements

Asphalt Pavements
How the FDR Works
Start With a Good Foundation
FDR Research in Progress

The Problems with Old Asphalt Pavements

Asphalt pavements eventually wear out. Just like old cars or clothing, the effects of wear and climate will destroy the pavement. The roads require costly maintenance to stay in service.

Asphalt pavements typically fail in several ways. The most common include:

Fatigue cracking Traffic causes repeated strain in the surface and eventually the asphalt cracks.

Rutting Channelized traffic loads shift the materials in the surface, base, and subgrade, leaving depressions or ruts in the pavement.

Shoving The forces created by cars and trucks braking and stopping separate the surface material from the underlying base.

Loss of base or foundation support Moisture degradation, traffic overloads, or subgrade failure can cause the pavement base to fail.

The type of failures mentioned above are especially prevalent in secondary roads, where pavement structures are typically light, and are often not designed for today's increased traffic levels. Repairs can be costly. A typical maintenance treatment, like a thin asphalt overlay, will only temporarily cover up the problem. Other options, such as thick overlays or removal and replacement, are expensive.

 

Text and Photos courtesy of Portland Cement Association www.portcement.org