Asphalt Berms in Construction: Function, Installation & Benefits
In construction and civil engineering, asphalt berms are specialized raised structures made of asphalt or asphalt-coated materials. Unlike traditional earth berms, these berms are designed for durability, resistance to erosion, and high structural integrity, making them ideal for a variety of infrastructure and site-management applications.
This article delves into what asphalt berms are, how they are constructed, their primary uses, advantages, design considerations, and practical installation tips. A comprehensive FAQs section follows the conclusion.
What Is an Asphalt Berm?
An asphalt berm is a engineered embankment or barrier formed from asphalt-treated materials, typically situated along roads, pavement edges, or around industrial sites. Constructed using asphalt concrete or recycled materials mixed with asphalt, these berms provide a durable, impermeable barrier resistant to erosion, water penetration, and vehicular impact.
Key Characteristics:
- Made from hot-mix asphalt or recycled asphalt pavement (RAP)
- Durable, impermeable, and low-maintenance
- Can support vehicular loads, chemical exposure, and moisture
Main Purposes of Asphalt Berms
1. Water Management & Drainage Control
Asphalt berms effectively channel surface water, creating curbs or channels that direct runoff to drains. Their impermeable nature prevents seepage and protects underlying soils.
2. Pavement Edge Restraint
They act similarly to curbs, holding edge pavement in place, preventing shoulder failure, and increasing pavement longevity.
3. Erosion & Sediment Control
In areas prone to runoff or washouts, asphalt berms act as permanent barriers that protect slopes and slopes’ integrity.
4. Vehicle Guidance & Safety
Commonly used in parking lots, internal access roads, and industrial yards, they help control vehicle paths and reduce damage to landscaping or structures.
5. Containment of Fluids or Leachate
When constructed with proper sealing, asphalt berms can contain spills, limit spread of chemicals, and improve environmental protection.
Construction Methods
Step 1: Site Preparation
Proper grading, base installation (like compacted aggregate), and slope assessment are essential before placing asphalt layers.
Step 2: Material Placement
- Hot-Mix Asphalt: Applied in layers similar to road paving, compacted with rollers.
- Cold-in-Place RAP: Reprocessed on-site, mixed with asphalt binder, and placed compacted.
Step 3: Compaction
Dense rolling ensures the berm is strong, impermeable, and capable of bearing loads.
Step 4: Finishing & Sealant
Once shaped and cambered, the top can be sealed with tack coats or asphalt overlays for enhanced durability.
Benefits of Asphalt Berms
- Exceptional Longevity: Concrete-like durability when properly installed and maintained
- Waterproof Barrier: Prevents water infiltration and safeguards soil foundations
- Structural Strength: Withstands vehicle contact and mechanical stresses
- Minimal Maintenance: Resistant to cracking, rutting, freeze–thaw cycles
- Speed of Installation: Especially with pre-fabricated or modular asphalt curb segments
- Environmental Adaptability: Recyclable and can incorporate sustainable RAP material
Design Considerations
| Factor | Consideration |
|---|---|
| Height & Profile | Designed based on drainage needs or curb height required |
| Material Mix | Standard HMA or RAP mix based on load requirements |
| Base Preparation | Subgrade must be compacted and properly graded |
| Slope & Alignment | Gentle side slopes and drainage gradients are essential |
| Compaction Standards | Must meet density specs (often ≥ 95%) to ensure durability |
| Seal Coating | Enhances longevity and reduces water penetration |
Common Applications
- Roadside Shoulders: Define edges and prevent edge breakdown
- Parking Areas: Separate landscaped islands and guide traffic
- Industrial Sites: Contain light fluids and define zones
- Airport Aprons: Provide durable edge restraints
- Landfills & Recycling Facilities: Serve as permanent perimeter or containment barriers
Installation Best Practices
- Conduct a soil/subgrade evaluation before berm design.
- Apply tack coat between lifts to ensure adhesion.
- Compact thoroughly using vibratory or rubber-tire rollers.
- Ensure drainage flow with slope gradients directing water to outlets.
- Inspect joints and edges to avoid water infiltration points.
- Apply seal coat within the first year to ensure durability.
Conclusion
An asphalt berm is a versatile, durable solution for controlling water flow, reinforcing pavement edges, and providing structural support where traditional earth berms may fail. Whether for drainage, containment, or edge restraint, asphalt berms deliver resilience and efficiency. Their low maintenance and long-term performance make them a smart investment across many construction and industrial projects.
FAQs About Asphalt Berms in Construction
Q1: What is an asphalt berm?
An asphalt berm is a raised, compacted structure made of asphalt or asphalt-treated materials, used for edge restraint, drainage control, and containment.
Q2: How does an asphalt berm differ from an earth berm?
Unlike earth berms made of soil, asphalt berms are impermeable, durable, and able to withstand traffic loads without erosion.
Q3: Where are asphalt berms commonly used?
They are often used along roadsides, parking lots, industrial campuses, airport aprons, and containment zones.
Q4: Can asphalt berms contain spills?
Yes—when properly designed and sealed, they can contain light fluid spills and reduce environmental risk.
Q5: Are asphalt berms easy to maintain?
Yes. They require minimal upkeep—typically periodic inspections and occasional seal coating.
Q6: Can recycled asphalt be used?
Yes. Reclaimed Asphalt Pavement (RAP) can be incorporated into the berm mix, promoting sustainability.
Q7: What is the typical lifespan of an asphalt berm?
With proper installation and maintenance, asphalt berms can last 15–25 years or more.
Q8: Do asphalt berms require drainage systems?
Yes, adequate slope and sometimes integrated swales or outlets are necessary to manage runoff and prevent pooling.
