There are many ways to tell the best asphalt driveway contractors from all the rest, but one of the most critical aspects that distinguish them is their willingness to test the bulk asphalt they’re getting from asphalt suppliers. Not all hot mix asphalt is the same, far from it. Quality in a supply can vary wildly. The best contractors, like Mt. Pleasant Blacktopping, know this, test their mixes, and will only supply top quality bulk asphalt to local contractors as well as use the best in all of their contracted jobs.
There are three aspects of hot mix asphalt that Mt. Pleasant Blacktopping monitors: gradation, binder content, and air voids.
The Three Most Critical Factors Asphalt Driveway Contractors Look for In Bulk Asphalt
1 – Aggregate Gradation
Very simply put, asphalt is made from chunks of material called “aggregates,” such as sand and rock and gravel, which are held together by a binding substance. Gradation refers to the minimum and maximum size of those aggregates. Different projects might call for larger or smaller aggregate gradations, based on the qualities desired in the final paving.
Asphalt suppliers will list the aggregate gradation of their products, but the bulk asphalt does not necessarily match up to those hypothetical listings. So, an asphalt contractor will test the mix for themselves, filtering out the larger aggregates to test their size. This allows them to properly match the mix to the project. Mt. Pleasant Asphalt is 100% Crushed Limestone.
2 – Binder Content
Just as the size of the aggregate makes a big difference to a piece of asphalt paving, so does the percentage of binding material. Too much binder can make asphalt which is too soft or even continues to flow outwards even after it’s set. Too little binder makes the asphalt weak and easily-cracked.
It’s vital that asphalt driveway contractors test the amount of binder in each mix, to ensure they are laying a reliable final product. Mt. Pleasant uses premium Marathon Performance Grade Binders.
3 – Air Voids
Asphalt mix has substantial air content, which is introduced to the hot mix asphalt during the mixing process. As with binder, air voids must be at a proper ratio. Too much air creates asphalt which is easily-compacted and unstable, while too little air will (like too much binder) encourage the asphalt to flow.
All three of these materials – aggregate, binder, and air – must be in proper ratios for reliable asphalt installation.