After I realized that our back porch was chipping apart, I decided that I needed to work a little harder to make things right. I started carefully analyzing the area, and I realized that the concrete needed to be completely removed and re-poured. I knew that asphalt work was beyond my comfort level, so I decided to call in a professional contractor to do the work. It was amazing to watch them work, and when they were finished our yard looked brand new. This blog is all about improving your hardscaping by replacing old, cracked, or discolored asphalt or concrete paving.
Perhaps the single most important factor in determining the longevity of asphalt pavement is its degree of compaction. Unfortunately, this is complicated by the fact that not all asphalts are equally compactable. Whether you are a paving engineer, or are simply a curious amateur, if you would like to learn more about the asphalt installation process, read on. This article will introduce you to two of the most important factors governing the compactability of a particular asphalt mix.
Type Of Mix
Contrary to many people's impression, not all asphalt is the same. It's true that distilled oil products and crushed stone aggregate make up the principal ingredients in all asphalt surfaces. But the size and proportions of these ingredients vary from asphalt to asphalt. Likewise, an array of different additives may be incorporated into a particular mix. Such additives act to determine the way the asphalt will behave, given its placement, intended use, and the weather it will be exposed to.
Where compactability is concerned, the size of the aggregate used is one of the most important factors. A dense graded mix--one that contains a variety of aggregate sizes in roughly equal proportions--presents a fairly easy surface to compact. An open grade mix, which omits medium sized aggregate particles, makes compaction more difficult. This reflects the fact that open grade mixes result in a "stiffer" asphalt--in other words, one that possesses a greater degree of resistance to cracking, rutting, and raveling.
Temperature Of The Mix
Asphalt mixes come in a variety of different temperatures, from hot to warm to cold. Among other things, the temperature of a particular asphalt mix has a direct effect on the compactability of that mix. This is true both in terms of the temperature at which an asphalt was produced, and the temperature changes an asphalt is subject to during the compaction process itself.
Asphalts produced at higher temperatures are generally more "tender" and easy to spread. This means that a much lighter rolling action is required from the drum roller, otherwise the asphalt will be more liable to cracks as a result of over-compaction. Stiffer mixes--those produced at low temperatures--require heavier rolling action and more passes from the drum roller.
While cold mix asphalt can be more difficult to work with, one of its principal benefits is that it is not as subject to temperatures changes during the application and rolling process. Hot mix asphalt, on the other hand, begins to cool as soon as it has been applied. It can be difficult to accurately compensate for the effect such temperature change swill have during the rolling process. For that reason, it is imperative that the asphalt be compacted as soon as possible, to minimize the degree of cooling. Talk to an asphalt contractor for more help.Share
15 July 2016