Both asphalt and concrete parking lots can suffer from unsightly and treacherous potholes if damaged or neglected. But how exactly do potholes develop? And what can property managers do to prevent the conditions that encourage potholes?
Here are the main phases in pothole development.
Phase 1: Damage Trigger
In some cases, the trigger for the initial pavement damage is a faulty foundation. If the pavement’s surface isn’t properly supported, even normal stress loads will overload the structural capacity of the pavement and allow cracks to appear. Of course, too much weight can also cause excess stress on a foundation that was originally supported correctly.
To prevent this damage, always install pavement with the best possible foundation so it can withstand high amounts of pressure and weight.
Another possible trigger that can kick-start a pothole is chemical damage from automotive liquids. If a car leaks engine oil while parked in your lot, the oil can react with the binders used to hold asphalt together. Keeping your pavement clean and occasionally resealing it can help avoid damage.
Phase 2: Water Intrusion and Foundation Damage
Once initial damage has breached the top layer of the pavement, water can start to intrude. Water can cause damage at multiple levels, which is what makes it such a formidable enemy. For example, water in surface cracks can force the cracks deeper when winter weather causes freeze-thaw cycles, until the damage reaches all the way through.
Once deep cracks have formed, water can interfere with the foundation (also called the sub-base or subgrade) of the pavement, even if the foundation wasn’t already faulty. For example, frost heave can occur once water reaches the foundation materials.
Repairing cracks before they reach this level is another way to keep damage from advancing into full-blown potholes.
Phase 3: Raveling or Crumbling
In this phase, both the original stressor and other forces like water and UV rays continue to develop pavement damage. More and more cracks may appear in this stage, and the area is likely to experience raveling as well, which is when the tiny aggregate particles that make up the asphalt start to work loose.
If your asphalt is raveling, you’ll be able to see many small particles and granules sitting loose on the surface of the pavement. This type of damage can be a sign that you should call for repairs.
Once sufficient amounts of the localized pavement structure have raveled and crumbled away, the pothole will start to become more defined as the loose pieces are carried away. Small chunks of asphalt may be knocked loose by traffic, and the raveling aggregate pieces can be washed away by rainwater.
Phase 4: Patching
Once a pothole has fully developed, it presents an obvious and visible problem spot in the pavement. If the hole isn’t repaired, the damage can spread and more pavement will require replacing. But if a professional repairs the pavement, you can reverse the damage as the pothole is patched and completely repaired.
Because a pothole affects all the layers of pavement, the professional repair personnel will need to patch instead of resurface or reseal. Some types of pothole repair include simply placing more pavement material on top of the hole, but that’s not the most stable solution.
For long-lasting results, your contractors will need to use a remove-and-replace style of repair. They’ll cut out the damaged spot and replace that entire section from the ground up. This repair technique includes fixing any problems with the foundation, which is especially important if foundation problems were the original trigger.
These are the four main phases of a pothole. If you catch the damage early on, you can typically stave off pothole development completely. However, even if your parking lot does develop one or more potholes, all you have to do is hire an experienced paving contractor to reverse the damage.
Pinnacle Paving & Sealing is available for both new installs and maintenance or repairs of current parking lots. For more information on our services, contact us today.