Asphalt is often used for parking lots, driveways, and roads because it lasts long and is good value for money. But weather, age, lack of maintenance, a lot of traffic, or even poor site preparation can sometimes cause problems.
Here, we look at some of the most common problems with asphalt paving, what causes them, and how to fix them.
THE BEST OFFENSE IS THE BEST DEFENSE
By doing regular maintenance, you can make your asphalt pavement last longer. Among these steps are keeping the surface clean, sealing it, and fixing problems as soon as you see them. But you have to know what the problems are with asphalt pavement before you can fix them.
Here are eight common problems with asphalt pavement, what causes them, and how to fix them.
- RAVELING
Have you ever walked through a parking lot and noticed loose gravel or grit? If so, you’ve probably seen raveling for yourself. Raveling is when asphalt and rocks fall out of the pavement and cause it to break down.
Over time, the pavement gets thinner and loose gravel wears away at the asphalt that is left. When gravel gets into asphalt, water seeps in and makes the problem even worse. Raveling can make the ground uneven (a trip hazard!) and cause water to pool.
HOW TO FIX RAVELING IN ASPHALT
The first step in fixing a raveled asphalt surface is to remove any loose material.
- If the hole is only in a small area, you can fix it with a simple asphalt patch.
- If there are large cracks in the pavement, it means that asphalt is failing everywhere. When this happens, the best long-term solution is to take out the damaged asphalt and put down new asphalt over it. This will need the help of a person who knows how to work with asphalt.
- DEPRESSIONS
Depressions are low spots on the pavement where the asphalt doesn’t go all the way through. They are usually caused by the way the asphalt was packed down when it was laid.
If they aren’t fixed quickly, the water and trash that tend to collect in depressions can wear down the asphalt surface and make it less stable.
HOW TO FIX DEPRESSIONS IN ASPHALT
- A simple asphalt patch can be put on top of the existing pavement to temporarily fix small depressions. But patching won’t fix the main problem, which is that the soil wasn’t packed down well enough, so the area may continue to sink.
- For asphalt depressions to be fixed permanently, the damaged area must be removed, the bad subgrade must be replaced, and a full-depth patch must be put over the subgrade.
- POTHOLES
Potholes are small, bowl-shaped depressions in the pavement surface that go all the way through the asphalt layer and down to the base course. The edges of potholes can be very sharp, and potholes in asphalt pavement get bigger over time as the water gets into the area.
Alligator cracking is usually what causes potholes in asphalt (also known as fatigue cracking.) When alligator cracking gets bad, the connected cracks make big chunks of pavement that can break off when cars drive over them. When a piece of pavement breaks off, the hole that is left behind is called a pothole.
One of the most common problems with pavement is these well-known safety hazards. The size and roughness of the pothole’s edges can cause serious damage to cars and make it hard for people to walk.
HOW TO FIX HOLES IN BLACKTOP
There are many ways to fix holes in the road. Two common ways are explained below.
TOSS-AND-ROLL
- Put the patching material in the hole without cleaning it or getting rid of any water or debris first.
- Patching truck tires are used to pack down the filling material (usually 4 to 8 passes).
- Check to see if the pressed patch has a small crown. If there is a hole, add more patching material and press it down.
SEMI-PERMANENT POTHOLE PATCH
- Take the water and trash out of the hole.
- Fix the edges of the potholes so that they are vertical and the pavement is still there on all sides.
- Put the patching material into the hole that has been cleaned and made square. The material should be higher in the middle and get smaller as it gets closer to the edges so that it fits flush with the pavement edges.
- Use a vibrating plate compactor or a single-drum vibratory roller to pack down the patching material. Start compacting in the middle and work your way out to the edges. Check that the patching material has a slight crown after it has been compacted. This is done so that when cars drive over it, it will be pushed down to the same height as the surrounding pavement.
- THE ALLIGATOR CRACKS
Fatigue cracking also called “alligator cracking” is a common way that asphalt pavement gets worse over time. It’s called an alligator crack because the cracks look like the scales on an alligator’s back.
Alligator cracking is a form of load-related damage that happens when:
- a weak base course or sub-grade,
- too little pavement thickness,
- overloading, or
- a combination of these factors
Once alligator cracks appear, the pavement will keep getting worse unless you do something about it.
HOW TO FIX ALLIGATOR CRACKS IN ASPHALT
- Crack filler or sealcoating can be used as a short-term fix to keep water and dirt from getting into the cracks and making them worse. Next, if you can, you should limit traffic in the area because cars driving over the weakened pavement will damage the asphalt surface even more.
- Alligator cracks in asphalt pavement can only be fixed permanently by digging down to find the problems and then strengthening the asphalt’s base. This is a job for trained professionals, who will take out the damaged asphalt and put it in a new sub-base and asphalt surface.
- LONGITUDINAL CRACKING
Longitudinal cracks in asphalt pavement are cracks that run in the same direction as the asphalt (along a driveway or road.) They can be caused by many things, such as:
- joints that were not made well
- Temperature changes cause asphalt to contract and expand, and
- cracks from a lower layer show through.
Longitudinal cracks in asphalt pavement have nothing to do with how much weight is on it.
HOW TO FIX ASPHALT CRACKS THAT RUN LONGITUDINALLY
Smaller cracks (less than 1/2 inch wide): Use a crack sealant to keep water from getting into the sub-grade layers through the cracks and to keep the crack edges from fraying. After filling the cracks, sealcoating should be reapplied to a larger area.
Larger Cracks (More than 12″ Wide): Hire an asphalt expert to figure out what’s causing your long, deep cracks and suggest a long-term fix.
- CRACKING BLOCK
Block cracking is a patch of large, rectangular cracks on the surface of an asphalt road that is about a foot or longer. This kind of cracking usually affects a large area and can happen even where there is no traffic because it is not caused by the weight of vehicles.
Blocks usually crack when the asphalt binder can’t expand and contract with changes in temperature because it has hardened with age or because the asphalt binder used in the mix wasn’t good enough.
HOW TO FIX ASPHALT BLOCK CRACKING
How to fix cracked blocks depends on how big and deep the cracks are:
Use a crack sealant to stop water from getting into the subgrade through the cracks and to keep the edges from raveling. After filling the cracks, sealcoating should be reapplied to a larger area.
If the cracks are more than 12″ wide and have jagged edges, you should hire a professional to remove the cracked pavement layer and replace it with an overlay. Browse around this site.
- EDGE CRACKS
Edge cracks are long cracks that form within one or two feet of the pavement’s edge. They are more common on rural roads and driveways than on city streets.
Edge cracking happens when there isn’t enough support at the edge of the pavement, and because rural roads and driveways tend to be narrow, cars have to drive close to these edges.
Edge cracks can also be caused by bad drainage, a bad base or sub-base, or asphalt that has shrunk. If you don’t fix edge cracks, they will get bigger and longer, and more will appear in the middle of the road.
HOW TO FIX CRACKS IN THE EDGE OF ASPHALT
Preventing edge cracks is much better than fixing them. Here are some suggestions for how to do this:
- Make sure the edge of the sidewalk has good drainage.
- Make sure you have a strong, well-connected base set.
- As soon as the asphalt has hardened, apply a layer of sealcoating to protect it from damage caused by weather, temperature changes, and general use.
Even if you do everything you can to prevent edge cracks, they may still happen. Here’s how to fix the problem:
- Minor edge cracks: As soon as you see a small crack, use a crack sealant to fill it.
- More serious edge cracks: Fix the damage by patching or replacing it in a way that fixes the cause of the edge cracks.
- UPHEAVING ASPHALT
Upheaval is a localized rise in the asphalt pavement that happens when the subgrade swells because of freezing or too much water. One example of this kind of stress is frost heave.
HOW TO FIX UPHEAVING ASPHALT
Since asphalt upheaval is caused by problems in the pavement subgrade, the best solution is to remove the damaged area and put down a full-depth asphalt patch.
At Hackensack Paving, we pave asphalt, fix asphalt, and take care of asphalt for residential, commercial, municipal, and industrial customers.
Call (201) 514-6060 during business hours to be sure of getting a response the same day.
