The Road to Good Asphalt Quality Control, Quality Assurance & Quality Acceptance

Table of Contents

• Step #1: Know Who's Responsible for What
• Step #2: Map the Route With a Quality Control Plan
• Step #3: Run Your Pre-Trip Checklist in the Field
• Step #4: Trust & Verify With Quality Assurance
• Step #5: Know the Difference Between Inspection & Testing
• Step #6: Check the Right Gauges

Like any successful summer road trip, getting from a good asphalt paving project to a great one takes the right prep before you leave the driveway, hitting the right stops along the way and answering, “Did we actually get where we were trying to go?”

That's the idea behind asphalt quality control (QC), quality assurance (QA) and quality acceptance. Although there's some real overlap between them, each plays a distinct role in ensuring an asphalt pavement project turns out the way it was designed to.

Here are six key steps to help keep your asphalt pavement project on the right track.

[ Video Coming Soon ]

Step #1: Know Who's Responsible for What

Every asphalt paving project involves producers and contractors who build the road, and local agencies who own the road (and are ultimately the customer it's being built for). Each side has a different role to play in ensuring the project sticks to the specs and the plans: how the work was bid, how it was constructed and how it was ultimately accepted.

Quality control, from a contractual standpoint, usually falls directly on the producer and the placer. It's their responsibility to make sure the road being built is the road that was promised. Quality assurance and quality acceptance, on the other hand, are the owner's responsibility. Knowing which side of that line you're on—and what's expected of you there—is the first step toward a project that goes smoothly.

Step #2: Map the Route With a Quality Control Plan

Just like a road trip goes better with a mapped-out route, a paving project goes better with a written quality control plan. It needs to name names on who's handling each part of QC, and it needs to be worked out before there are materials, crews and equipment already in the field. Trying to figure it out on the fly is a recipe for a rough trip.

A solid QC plan covers the material submittals and mix designs, but the centerpiece is the pre-pave meeting. This is where the whole team gets on the same page: when tests will be run, who's running them and who's responsible for reporting the results and to whom.

Think of it as mapping your route before a road trip—deciding where you're stopping for gas, what happens if there's construction ahead and what the plan is if something doesn't go the way you expected. Working those scenarios out ahead of time is a lot easier than working them out on the side of the road.

Step #3: Run Your Pre-Trip Checklist in the Field

Before a road trip, you check your oil, look at your tire pressure and make sure there's enough gas to get to the next stop. Quality control in the field works the same way.

It starts at the plant, with a suite of tests to confirm that the material being produced meets the required quality standards. From there, the asphalt quality control plan should account for how the mix is trucked from the plant to the field and what happens once it arrives. This includes how it gets in front of the paver, how it gets placed, and how temperature and compaction are checked along the way. Skipping any one of these checks is a lot like leaving on a summer road trip without checking your tires—you might make it, but you're taking on a risk you don’t need to.

Step #4: Trust & Verify With Quality Assurance

A lot of the tests run for quality assurance are the same as those run for quality control, but the objective is different. Quality control is about process control and asking, “Are we building it right as we go?” Quality assurance and quality acceptance ask, “Can we accept this work?”

It's common to see a local agency rely solely on contractor or producer test results as its form of quality assurance. That's better than nothing, but it’s not the same as owner verification—the "trust, but verify" approach that gives an agency its own set of eyes on the project. That means making sure the technicians running tests, whether on the QC or QA side, are properly certified, and that testing and reporting are built into the project from the start.

So, are we there yet? Not quite. Even a project built to spec with a technician on-site still needs someone asking whether the finished work actually meets the standard it was supposed to meet. That's what quality acceptance is for.

Step #5: Know the Difference Between Inspection & Testing

Inspection and testing often get lumped together, but they aren't the same job. A testing technician runs a standardized test using a density gauge, a straightedge, a thermometer or other equipment to measure a specific parameter. An inspector observes and documents the process to determine if it was followed the way it was supposed to.

Some experienced technicians can do both well, using years of field experience to spot a problem before a test even confirms it. However, a newer technician can run a test perfectly and still lack the inspection experience to know what to watch for. Local agencies should make sure whoever is representing them in the field, whether in-house staff or an outside testing lab, has genuine experience as an inspector, not just as a technician.

Step #6: Check the Right Gauges

A handful of tests carry a project from the plant to the finished road. At the plant, that means checking gradation, inspecting asphalt content and running a lab density check using a Superpave gyratory press to see what's achievable under ideal conditions. In the field, it means tracking temperature and checking density and thermal segregation, including along the longitudinal joint.

At the end of the process, a core sample ties it all together. Asphalt core testing allows a density and thickness check against the finished product requirements, and it should reflect the properties approved in the original mix design. It's also what helps calibrate the quicker, more frequent density gauge checks that don't require pulling a core every time.

For more asphalt pavement industry insights, subscribe to our YouTube channel and tune in to our newest podcast, Road Maps for Texas Local Agencies.