Timing is everything. Investing in preventative maintenance methods while bituminous/asphalt pavement is still in good condition can save money over the life of the pavement. The U.S. Department of Transportation’s Federal Highway Administration (FHWA) recommends having preventative maintenance programs in place as soon as asphalt pavement is installed.
The service life of asphalt pavement ranges from 15 to 30 years. From the moment it is installed or placed, asphalt pavement begins to cure and age. There are many factors that affect the longevity of asphalt pavement; geographic location and environmental factors, construction method and materials used, and type of maintenance methods implemented.
Depending on the existing condition of the asphalt pavement, maintenance methods may include the following: surface sealing, localized patching, crack filling, mill and overlay, Examples of maintenance are as follows:
As the pavement ages, tensile stresses increase within the asphalt, which ultimately will exceed the tensile strength of the asphalt itself. This will cause the asphalt to become brittle, resulting in pavement distresses, such as full-depth cracks and rutting/raveling in the vicinity of the weakness. Weakness can occur along asphalt cold joints between paving applications or pours, and along irregularities in pavement thickness. Over time, the rate and extent of pavement distress accelerates, and with water intrusion and ultraviolet radiation, the asphalt is subjected to more rapid deterioration.
Crack sealing and surface sealing are two types of preventative maintenance methods used to improve and extend the life of the asphalt pavement. Without a proactive maintenance plan, longer periods between maintenance efforts may result in pavement so deteriorated that preventative maintenance is no longer a viable option. At that point, complete reconstruction may be required. Implementing preventative maintenance methods early and often is a cost-effective approach to prolong the life of the asphalt pavement. Professionals knowledgeable about the evaluation, design, and construction of bituminous asphalt paving can prepare a preventative maintenance strategy to help extend the service life and costs associated with paving.