Maintaining the asphalt in your parking lot takes time and effort, and it helps to understand the culprits causing the most problems. The surface will deteriorate naturally over time, but many factors can shorten the lifespan of your parking lot. Knowing what contributes to the breakdown can help you prioritize your maintenance strategy.
Enemy #1: Heavy traffic weighs down the surface
Pavement can experience fatigue failure because it bends with the weight of vehicles, and consistent exposure to heavy wheel loads can damage the surface. A parking lot will last longer if there is traffic from lighter vehicles, but that is not the case if semi trucks are regularly traversing your property.
One strategy is to designate an area for truck deliveries. Use a stronger subgrade with more layers of asphalt to compensate for the heavier traffic.
Enemy #2: Poor installation significantly reduces your parking lot’s lifespan.
It is possible for errors during the installation process to cause a plethora of parking lot problems
A weak surface or subgrade can cause early alligator cracking that can only be remedied with a full-depth patch.
If the mix was too dry when it was placed, then the pavement may experience more block cracking.
The wrong grade of asphalt or too much asphalt in the mixture will cause corrugations and shoving.
Improper construction technique could result in grade depressions (bird baths).
It is important for a contractor to use the right type of asphalt for the area and climate. They must also place enough layers for the expected traffic volume. If you are looking to install a parking lot, thoroughly vet the Norman or Oklahoma companies you are considering to hire. Make sure no one compromises on quality, and the paving project is well-planned.
Enemy #3: Oil and gasoline spills breakdown the bitumen.
An oil spill may seem like nothing more than a harmless stain, but it quickly begins breaking down the bitumen in your asphalt. The chemicals in oil and gasoline cause the pavement to soften. Act quickly when you notice a spill. Soap and water will often do the trick on cleaning it up, but so will kitty litter or a power washer.
Asphalt Rejuvenator will project your parking lot for absorbing these spills, and consequently, keep your maintenance expenses lower.
Enemy #4: Oxidation begins to deteriorate the surface immediately.
Oxygen causes a process called “self-assemblage” in asphalt. The molecules move about to create bonds and achieve a thermodynamic stable state. Over time, the surface begins to harden and becomes stiffer, more brittle and prone to cracking.
An oxidized asphalt surface loses its load bearing capacity, and it eventually it results in fatigue failure or other types of unraveling.
Enemy #5: Moisture damages good asphalt.
Water is the ultimate solvent, and if your parking lot does not drain properly, water will seep into the cracks and cause further damage to the surface. It is a misconception to think that asphalt is waterproof. In fact, it is one of the worst enemies to your parking lot because it can weaken the foundation. Furthermore, if water gets caught in the pavement in cold climates, it can freeze, expand and bust open the surface.
Enemy #6: Weather patterns wreak havoc.
Okay, you can’t change the weather, but you can control how you react to it. Every season brings new challenges to your parking lot, and you should be prepared to protect it from the elements. In Oklahoma, weather is erratic freezing temperatures and steaming summers can do a number on your parking lot. However, you can implement a few strategies to prolong the pavement.
Asphalt loses the most strength in the springtime as the ground thaws in cold climates. The weakening of the subgrade soil accompanied by an increase in traffic is a recipe for pavement damage. The type of subgrade you use will determine how much your pavement is affected. A subgrade consisting of mostly sand will stay stronger compared to soil made of silt or clay.
Winter and summer are not kind either.
During the coldest months of the year, deicing agents help keep parking lots from becoming a slipping hazard. However, these chemicals result in stripping because they break down the bonding agent in the asphalt.
Magnesium in many deicing products can cause long-term effects because it speeds up the natural deterioration of the surface. Sand dumped to help people and cars gain traction can also get into joints and cracks of the pavement and exasperate existing problems.
Your parking lot experiences the most wear and tear on hot summer days. Longer days mean more UV exposure. UV rays burn off the essential oils that keep the surface flexible. While a harder surface seems like a good thing, it’s not. If the surface becomes too dry and brittle, it is more susceptible to cracking.
When you start noticing a lot of gravel in your parking lot that is how you know the binder is deteriorating from one of these culprits.
All of these work together to cause cracking
There are more than a dozen different forms of asphalt deterioration, and each hints at a different problem. To name a few:
Fatigue cracking, or alligator cracking, is a severe problem that can cause a full structural failure.
Slippage cracks look like stretch marks on the asphalt. This results from a weak binding agent between layers due to dust, oil, rubber, water or dirt.
Longitudinal and transverse cracking can occur as the result of daily temperature cycling, shrinkage of the asphalt layer or an inadequate paving joint.
Potholes often occur after a time of freezing and thawing.
The best defense against the most common enemies of asphalt is regular parking lot maintenance such as asphalt rejuvenation. Download our guide about the differences between asphalt rejuvenation and sealcoating for help prioritizing your pavement projects.