Industrial-Strength Asphalt

Heavy trucks put a serious strain on asphalt. If yours isn’t built tough and to the correct grade, it will crack, break, and need constant repairs. At Asphalt Doctors, we know what it takes to build pavement that lasts under the toughest conditions. Here’s what you need to know. 

Why Heavy Truck Traffic Demands Special Pavement Design

Heavy trucks can weigh up to 80,000 pounds or more, putting enormous pressure on pavement—sometimes over 10,000 pounds per tire. Add in frequent stops, sharp turns, and shifting weight, and the stress on the pavement multiplies.

When pavement isn’t built for this kind of punishment, it starts to break down, causing cracks, and potholes to develop. These issues cost you time and money in repairs and downtime. That’s why designing pavement specifically for heavy truck traffic matters. It keeps your surfaces safe, operational, and durable.

How to Choose the Right Grade of Asphalt for the Job

When we talk about “grades” of asphalt, we’re really referring to different mix types (or “asphalt gradations”) and how they’re engineered to respond to load, environment, and long‑term performance. In industrial or heavy‑use settings, it’s especially critical to choose a mix that stands up to high stress, traffic, and potential for deformation.

Below is a breakdown of the common categories and a guide to selecting the correct mix for each project.

Additionally, within dense‑graded mixes, the “nominal maximum aggregate size” (NMS) is used to classify mixes: e.g. 9.5 mm, 12.5 mm, 19.0 mm, 25.0 mm, 37.5 mm, etc. The larger the NMS, the more coarse aggregate, which can resist heavier loads but has trade‑offs in texture, compaction, cost, and appearance.

Most asphalt paving jobs—especially industrial, commercial, or roadway projects—use multiple types of asphalt mixes layered together. This is standard best practice, and it’s done to optimize performance, cost, and durability for different parts of the pavement structure. So the top layer can use any of the above types of mixes but most likely an open-graded mix, the intermediate course will use dense-graded mixes, and the base course will use even more coarse and denser mixes to establish structural stability. 

Determining What Grade You Need: A Step‑by‑Step Approach

Here’s a simplified process you can follow when specifying asphalt for a project: 

1. Estimate the Required Pavement Thickness / Structural Need

For new construction, run a structural design to find how thick your asphalt layers need to be to carry the design loads. For rehabilitation, evaluate the existing structure and determine how much overlay (or how deep replacement) is required. If you’re not sure, it’s best to work with an asphalt contractor with the knowhow to get you the correct asphalt design your project needs.

2. Classify the Expected Traffic / Load Level

The Federal Highway Association (FHWA) uses ESALs (Equivalent Single Axle Loads) over 20 years to categorize traffic:

• Low traffic: < 300,000 ESALs
• Moderate traffic: 300,000 – < 10,000,000 ESALs
• High traffic: ≥ 10,000,000 ESALs

Heavy truck traffic, slow-moving loads, or industrial traffic intensifies demands (e.g. more risk of rutting).

3. Choose a Mix Type for the Surface Course

For low traffic, dense‑graded mixes are almost always sufficient. For moderate traffic, dense‑graded still works well, though at higher end you might consider SMA or open-graded with friction course (especially if friction or drainage is desired). For high traffic (especially with trucks or slow loads), any mix type is a candidate, but SMA often becomes attractive for its rut resistance.

You’ll also need to decide the size of the aggregate: heavier traffic favors coarser aggregate (e.g. 19 mm, 25 mm, or thicker) to resist deformation.

4. Subtract Surface Course Thickness and Select Mix Types for Underlying Layers

From the total thickness, subtract what you’ll allocate to the surface course. The remaining thickness must be allocated among intermediate (binder) or base layers. For each remaining layer, reference mix type suitability tables to pick an appropriate mix. See figure 3 in the Federal Highway Administration’s guide.

Continue “building downward” until you’ve assigned all required layers.

5. Consider Additional Variables

• Surface texture / friction: If skid resistance is critical, you may choose a coarser surface or an open-graded frictions course overlay.
• Drainage / permeability: In some regions with high levels of precipitation, an open-graded overlay can relieve hydrostatic pressure or reduce splash.
• Material availability / cost: Premium mixes (like SMA) or special additives may be more expensive, so balance performance vs. budget.
• Local climate / thermal stresses: In areas with large temperature swings or freeze–thaw cycles, like Colorado, mix design (binder choice, air voids) becomes even more important to maintain durability in the long run.
• Existing substrate / rehabilitation constraints: If the existing surface is cracked, you may need to remove or repair with asphalt maintenance services before overlaying a particular mix type.

Ready to Build Pavement That Lasts?

Heavy truck traffic demands pavement that won’t quit on you. Don’t settle for quick fixes that lead to costly repairs down the road. Contact Asphalt Doctors today to get a customized asphalt solution designed for strength, durability, and long-term performance. Let’s make sure your pavement works as hard as you do.