Asphalt is a layered system carefully designed for durability and load-bearing strength. If any of these layers fail, the structure is compromised. Typical asphalt layers consist of:
- Surface Layer – The visible top layer that provides a smooth, rideable surface.
- Base Layer – A compacted layer of crushed stone or gravel that provides structural support.
- Subgrade – The natural soil beneath, which must be properly prepared to prevent shifting and instability.
If any of these layers fail, the entire pavement structure is compromised. That’s when issues like sinking, cracking, and potholes start to appear.
Common Causes of Subsurface Damage
1. Poor Drainage
Water is asphalt’s worst enemy, and if it seeps beneath the surface, it can erode the base layer, weakening the pavement above. Improper drainage systems or clogged catch basins can lead to standing water, accelerating this damage.
2. Weak or Improperly Compacted Subgrade
If the subgrade isn’t properly compacted before asphalt is installed, it can shift over time, leading to depressions, cracking, and uneven surfaces.
3. Heavy Traffic and Load Stress
Consistently heavy vehicles—like delivery trucks or buses—put significant strain on the pavement. If the base layer isn’t designed to handle the load, the pressure can cause premature deterioration.
4. Freeze-Thaw Cycles
In colder climates, water that seeps into small cracks can freeze and expand, putting pressure on the layers below. This causes pavement to buckle and crack, leading to potholes and surface damage.
5. Aging and Natural Deterioration
Over time, even well-installed asphalt will degrade. Oxidation, weather exposure, and years of wear and tear weaken the subsurface layers, requiring maintenance to prevent failure.
Signs Your Asphalt May Have Subsurface Damage
- Because subsurface damage isn’t always visible, knowing what to look for can help you catch issues early. Warning signs include:
- Depressions or sunken areas – Indicates base layer failure.
- Cracks that keep returning – Suggests structural issues below the surface.
- Potholes forming in the same spots – A sign of weakened subgrade or base layers.
- Pooling water – Indicates poor drainage, which leads to erosion.
- Uneven or wavy surfaces – Suggests shifting subgrade.
How to Prevent and Repair
- Invest in Proper Installation
Ensuring your asphalt is installed with a well-compacted subgrade and properly layered materials is key to long-term durability. Cutting corners on installation often leads to expensive repairs down the road.
2. Maintain Proper Drainage
Keeping drainage systems clear and ensuring proper slope grading prevents water from seeping into the base layers. Regular inspections help catch issues before they escalate.
3. Use the Right Asphalt Mix
Certain asphalt blends are designed for heavy loads or extreme weather conditions. Choosing the right material for your lot or roadway can make a significant difference in longevity.
4. Conduct Regular Inspections and Repairs
Routine inspections allow you to identify potential problems before they lead to major damage. Crack filling, pothole patching, and rejuvenation treatments help extend the life of your pavement.
5. Strengthen the Base When Needed
If your asphalt experiences frequent failures, reinforcing the base layer or adding geotextile fabric can improve load-bearing capacity and reduce future damage.
Protect Your Asphalt from the Ground Up
Subsurface damage can turn a seemingly fine asphalt lot into a costly repair project. The best way to prevent these issues is through proper installation, ongoing maintenance, and proactive repairs.
If you suspect subsurface damage in your pavement, BlakRoc can help. We specialize in evaluating, repairing, and reinforcing asphalt structures to ensure long-lasting durability.
📞 Call or text BlakRoc at (208) 409-8007 to schedule a consultation. Let’s keep your asphalt in winning shape! If you haven’t already follow us on Instagram for more asphalt content!
