The 6 Steps to Successful Asphalt Pavement Project Scoping & Development

Table of Contents

• Step #1: Know What You're Trying to Accomplish
• Step #2: Collect Your Data
• Step #3: Fill in the Gaps With Nondestructive Pavement Testing
• Step #4: Keep Traffic in Mind
• Step #5: Address Drainage and Site Conditions Up Front
• Step #6: Let the Data Drive Design (& Be Specific in the Bid Package)

We all know that Texas roads take a real beating. Growing communities, heavier truck traffic and unforgiving summers put real demands on asphalt pavement, and the projects that hold up aren't just well-built—they're well-planned.

From the first site visit through design, here are six steps to follow to successfully develop and scope your asphalt pavement project.

Step #1: Know What You're Trying to Accomplish

A complete, thorough bid package is ultimately the end goal, but you can't build one without first understanding the problem you're trying to solve. This means resisting the temptation to default to a cookie-cutter approach, like automatically calling for a mill and overlay just because a pavement looks a bit worn.

Local agencies sometimes make assumptions based on as-built plans that don't reflect what's actually in the ground. Layer thicknesses, conditions across a cross-section and other factors can vary dramatically from one end of a project to the other. Getting a clear picture of what you're working with is the only way to build an accurate bid package.

Step #2: Collect Your Data

Once you've narrowed down your project's goal, it's time to start collecting data.

On the visual side, engineers assess pavement distress by looking for cracking, rutting and other surface conditions that are less than desirable. From there, coring gives you a clearer picture of what's underneath: how thick the layers are, the types of materials present, the base’s condition and whether or not the subgrade was ever stabilized.

Data collection tells you which parts of the existing pavement structure you can reuse and which parts need to go. That question has major budget implications, and you can't answer it without collecting your data.

Step #3: Fill in the Gaps With Nondestructive Pavement Testing

Destructive sampling, like auguring through pavement layers and pulling physical samples, is valuable, but it's not your only option. Two nondestructive pavement testing methods worth knowing include:

Falling Weight Deflectometer (FWD) Testing

Falling weight deflectometer (FWD) testing measures pavement stiffness at set intervals (typically every block or 100 feet for project-level work). You can correlate that data against your boring results, which means you can take fewer borings and still get a reliable picture of conditions across the entire length of your project.

Ground-Penetrating Radar (GPR)

Ground-penetrating radar uses a radar apparatus to scan the pavement surface, either mounted on the front of a van or rolled across on a cart. By using different frequencies to scan different depths and resolutions, GPR is particularly effective at mapping thickness variability. It’s also helpful for spotting water trapped within pavement layers—a major hidden contributor to structural problems.

Step #4: Keep Traffic in Mind

Traffic data is one of the most underemphasized parts of pavement scoping (and one of the most important).

Agencies that haven't updated their design guidance in years may be working from traffic counts that no longer reflect reality. Here in Texas, where communities are growing quickly and truck traffic is growing right along with them, this can be a grave mistake.

Understanding not just current traffic, but future traffic is essential to designing a pavement structure that holds up over its intended life.

Step #5: Address Drainage and Site Conditions Up Front

Drainage is one of the leading causes of premature pavement failure on rehab projects.

If poor drainage contributed to the deterioration of the existing roadway, resurfacing without addressing the root cause means the new pavement will likely fail early, too. Borrow ditches get clogged, and culverts stop functioning. If you don't address these issues before you resurface, the road will show it in a few years—nobody wants a two-year-old road that looks like it's 10.

Drainage isn't the only site condition that needs attention up front, either. Before design begins, you need to consider pavement crown and sheet flow, curb and gutter tie-ins, driveway and intersection connections, right-of-way constraints and the amount of handwork required. All of this feeds into the bid package and affects whether contractors can bid the job accurately and execute it cleanly in the field.

Step #6: Let the Data Drive Design (& Be Specific in the Bid Package)

Once you've collected your data, design becomes a matter of math and iteration: figuring out which existing materials you can reuse, which thicknesses you need to handle anticipated traffic and where new material is required. Selecting the right mix type for each layer, whether that's a dense-graded mix, a Superpave mix or something more robust near the surface, is a critical part of this process.

Most projects don't fall neatly into the categories of "replace everything" or "leave everything alone." Often, only a portion of the base has failed, and you must clearly convey that nuance in the bid package.

Timing matters here, too. The longer the gap between data collection and construction, the more the pavement deteriorates, and the less accurate those original quantities become.

Proper project scoping isn't glamorous, but it's the foundation that everything else is built on. By keeping these six steps in mind, you can create a clear scope and a long-lasting asphalt pavement.

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