Asphalt pavements deteriorate in two ways. All pavements age from the effects of Mother Nature. Infrared rays from the sun cause the semi-solid asphalt particles to harden and become brittle. Cold temperatures cause the asphalt mat to contract creating thermal cracks. Over time, cyclic temperature changes lead to block cracking. Moisture induced damage will also cause the pavement to deteriorate over time.
Pavements can also deteriorate through loading. This is usually a concern on high volume arterial routes and highways that accommodate heavy vehicles (with 18,000 pound axle loads). Lighter vehicles (cars, pickups and SUVs) have an insignificant role in the load induced deterioration of the pavement.
As an asphalt street ages it remains in good condition for about 70% of its life. After that the pavement deteriorates at a rapid rate. Many pavement managers time their maintenance treatments to coincide with the “Treatment Triggers” shown on the following curve. By applying a low cost surface treatment on a street when it is still in fairly good condition an agency can realize significant savings in lieu of waiting for the pavement to deteriorate to the point when it needs to be paved or reconstructed.
If you would like to evaluate various pavement maintenance scenarios, please call us at 314-219-7305 or use our contact page.