Q. What is asphalt?
Asphalt (also known as bitumen) is a sticky black or dark brown form of petroleum that can be found in natural deposits as well as refined from crude oils. With the consistency of cold molasses, asphalt is most commonly used as the glue or binder when mixed with aggregate particles to form asphalt concrete (AC) for road construction. Technically speaking, parking lots and roadways are paved with asphaltic concrete although the term “asphalt” generally refers to the finished product and is commonly understood to be as such.
Q. What are the main benefits of asphalt?
Asphalt is faster and less expensive to construct than other pavement alternatives. Additionally, from a maintenance perspective, asphalt maintenance is easier and less expensive than alternative options. Equally important is the fact that asphalt is flexible and thereby creates a smoother ride for vehicles, reducing wear and tear on tires.
Q. What causes asphalt pavements to fail?
There are numerous things that can cause a pavement system to fail including poor initial construction, improper drainage, usage patterns, inadequate thickness of the asphalt concrete and/or lack of proper maintenance. With all that in mind, water is the main enemy of asphalt and any penetration through the asphalt and into the sub soil will result in the deterioration of the pavement.
Q. What is the purpose of sealing asphalt?
Applying sealcoat is essential in the maintenance of your asphalt. One benefit is that it provides a wearing surface on top of the asphalt concrete, helping with the preservation of the asphalt pavement below. Sealcoat essentially replenishes the fine aggregate and oil that has been removed from the surface due to traffic and water runoff. The seal also prevents moisture from penetrating the surface of the asphalt and beginning the process of deterioration. From an aesthetic stance, sealcoat will also revive the asphalt and return the black color that we generally associate with asphalt.
Q. What is the difference between asphalt, asphalt concrete and asphalt pavement?
In simple terms, asphalt is the glue or binder that is mixed with aggregate particles (or crushed rock) to create asphalt concrete. Asphalt pavement is a layer of asphalt concrete that is placed over a supporting base course consisting of crushed rock, gravel, Portland Cement Concrete (PCC) or various other specifically defined materials.
Q. What is the typical lifespan of asphalt pavements?
On average, asphalt pavement will remain intact for 20-25 years although several factors can affect this prediction including but not limited to climate, traffic patterns, the performance of proper maintenance, proper subgrade preparation, etc.
Q. How can I protect my investment in my asphalt pavement?
A proper maintenance schedule is very important in order to protect your asphalt pavement and maximize the lifespan. Industry standards suggest crack filling and sealcoating every 1-3 years, more in depth repairs every 4-6 years and removal and replacement every 20-25 years depending on traffic, weather, soil conditions and many other factors.
Q. How quickly can sealcoat support traffic?
Depending on weather conditions, and assuming that the sealcoat was applied on a dry and relatively sunny day (above 65 degrees), sealcoat will support traffic within 24 hours.
Q. How long should I wait to sealcoat new asphalt pavement?
In order for asphalt to properly cure, a newly paved asphalt section should be allowed a minimum of 3 months and up to a year before any seal is introduced. The oils within the new asphalt will need time to cure and if sealcoat is applied, it will prevent this process and result in a softer pavement system which will in turn be more susceptible to failure. In cases of an asphalt overlay, where the asphalt section is generally thinner, it is recommended to wait a minimum of 1 month for asphalt to cure.