Pavement maintenance and repairs become progressively and exponentially more expensive to remedy the worse they get, which underscores the importance of having a good preventative maintenance strategy.
Industry experts and engineers utilize a so-called “Pavement Condition Index” or PCI to assess the overall condition of a pavement structure. The scale runs from 0-100, with brand-new properly-installed pavements registering a 100 on the scale and working their way down from there. While the scale utilizes a qualitative method for assigning a value, it nonetheless provides a nice benchmark in determining a maintenance strategy and cycle.
The Asphalt Institute defines pavement maintenance and repair as “routine work performed to keep a pavement, under normal conditions of traffic and forces of nature, as nearly as possible in its as-constructed condition.” That is to say, keep it as close to 100 on the PCI as possible… It is recommended to keep that score registering around the 70 threshold or above because repairs begin to become reactive rather than preventative and consequently more expensive when below 70.
In the PCI cycle, the Asphalt Institute classifies three types of pavement repairs: maintenance, rehabilitation, and reconstruction. Rehabilitation can typically cost 10 times as much as maintenance and reconstruction can cost much more than that.
An effective preventative maintenance program involves (in increasing order of importance) crack filling, drainage management, patching, and seal coating. See our article titled “Examining the top three enemies of pavement: Water, water, and water” for more useful information on this topic. Most pavement problems start with small cracks which ultimately lead to widespread cracking after moisture intrusion. The Asphalt Institute estimates that once approximately 20 percent of a pavement structure shows “alligatoring” cracking at the surface, preventative maintenance and patching becomes useless because there is more widespread damage underneath that isn’t visible at the surface, and rehabilitation is then required. All “alligator” cracking starts underneath the pavement in the sub-base or sub-grade and works its way upward to the surface. So pavements can have all sorts of invisible, yet imminent, problems.
In its 7th Edition of The Asphalt Handbook, The Asphalt Institute provides this illustrative analogy which serves as a good summary of the importance of preventative maintenance: “A good analogy for preventative maintenance is the painting of a house. When the paint fades, it is repainted; the responsible homeowner does not wait until the paint is cracked and peeling. As with painting a house, the effectiveness of the preventative maintenance is directly related to the condition of the pavement.”