How are potholes in asphalt patched?

Potholes can be a significant safety risk. Whether in a private area such as a neighborhood or driveway or in public spaces such as parking lots and highways, they must be repaired as soon as possible. The most common method of fixing potholes is asphalt patching, due to its efficiency and cost-effectiveness. 

It’s not worth leaving a pothole to grow and cause more damage! From the experts at Asphalt Doctors, here’s all you need to do about how asphalt potholes are patched. 

What is a pothole? 

Any asphalt surface, including parking lots, driveways, roads, highways, and footpaths, can develop potholes. A pothole is a depression in the surface of asphalt where the tar has worn away, most often through extensive use, heavy weight, or weather erosion. Potholes can cause damage to the tires on bikes and vehicles along with a car’s alignment, suspension, and framework. 

Potholes can cause a car to swerve or veer slightly, leading to hundreds of road accidents every year. Furthermore, the potholes can grow and size and cause other structural issues if left unattended. It is, therefore, crucial that swift and effective repairs are made.

How do potholes form? 

Potholes can form when cracks develop on an asphalt surface. Heating during the day and cooling at night (along with similar seasonal temperature patterns) can cause the asphalt to expand and contract which causes the cracks to form. Water from rain, snow, and frost enters these cracks and, when the temperature drops below freezing, will cause the cracks to expand, creating more damage. As stress is added with continual traffic and the weight of moving vehicles, these cracks can grow further, developing into larger holes - also known as potholes. 

Methods of Pothole Repair 

There are several different methods used to repair potholes, including skin, infrared, and full-depth patching. 

Surface “Skin” Patching

Skin patching is a quick method for repairing minor defects in asphalt surfaces, such as low areas, depressions, minor rutting, delamination, and slight deterioration. This method replenishes the top layer of asphalt. 

Infrared Patching

Infrared patching is used for critical repairs such as high-traffic area potholes, pavement heaving, uneven surfaces surrounding catch basins, and rough surfaces. This method allows for deep penetration asphalt repair in a short period of time. 

Full Depth Patching “R&R”

Full-depth patching is a patching method for major displacement, faulting, alligatoring, potholes, and other asphalt defects that require the asphalt to be patched at its full depth. This method completely removes and replaces damaged asphalt.  

How Potholes in Asphalt Are Patched 

How potholes are patched will vary slightly depending on the solution chosen, but they all follow a general set of steps. 

Step 1 - Check the Condition of the Foundation

Some asphalt surfaces, such as footpaths, may be different, but most asphalt surfaces are laid on top of a foundation of compacted gravel that sits above the soil layer. An evaluation of the condition of the foundation will ensue before beginning any repair work. 

Step 2 - Cut Edges and Square the Perimeter of Damage 

All damaged asphalt will need to be removed including the surrounding space which likely has cracks - any cracks that remain could cause the pothole to reform and become worse. Using an asphalt saw and hammer, a professional team will remove all damaged asphalt, specifically in the shape of a square or rectangle which will last longer than other shapes. 

If performing a surface patch for spaces with minimal damage, no asphalt will be removed - a new layer will simply be applied over the surface. If performing an infrared patch, the existing damaged material will be heated and reused on the spot with a mixture of new asphalt material. 

Step 4 - Clean the Area and Remove Damaged Material (Full-depth only)

Once all damaged material has been removed and the area has been squared off accordingly, the area will be cleaned including all dust, debris, and plant life. Roots need to be carefully removed in order to prevent plants from growing through cracks or the patch. 

Step 5 - Repair Foundation (Full-depth only)

Now that the area is properly excavated and cleaned, the foundation must be repaired if there is any damage. Top up the foundation with a mixture of gravel and sand, then tamper and compress it accordingly to create a flat surface. Be sure to use a level to check that the foundation is properly repaired. 

Step 6 - Repair Surface

Surface patching will begin by applying CSS-1H tack coat to the repair surface, followed by a hot asphalt plant mix which is feathered and compacted appropriately. The work is finished by being neatly squared off. 

Infrared patching utilizes an infrared heating unit to heat the damaged surface over 6-12 minutes after it has been treated with a reclamite rejuvenating agent. A new hot asphalt plant mix is added to the existing asphalt, and the repair area is raked, tamped, and treated. Finally, the finished product is compacted at least twice in accordance with industry standards and squared off. 

Full-depth patching will apply CSS-1H tack coat to exposed vertical surfaces once all damaged asphalt material has been removed. Several layers of new asphalt plant mix are added to the repair area and compacted thoroughly with each application. The job is finished by squaring off the repair area. 

Step 8 - Haul Away and Recycle Old Material

After the asphalt surface is repaired, all the old, unused material is hauled away from the repair site in order to be recycled. 

Step 9 - Clean Up and Surface Preparation

All debris resulting from the process will be cleaned and the surface will be fully prepared for future use. 

Put Your Trust in the Asphalt Doctors

The family-owned team at Asphalt Doctors knows just how important it is that our asphalt surfaces are repaired as efficiently and effectively as possible - that’s why we only use the best practices and materials, and why we hold ourselves to the highest professional standards. We care deeply about our customers, employees, suppliers, and contractors. Contact our team today to schedule your asphalt patch and to learn why our clients love working with us.