Road damage could be split pavement, potholes, or just general road deterioration. If you have been hired to repair a road in front of a home, you may need to use a tack coat during the reconstruction. Below is some information about this to help you decide if this is right for the job you are doing.
One Cause of Road Damage
There are many things that can cause road damage, such as road deteriorating over time, heavy traffic, and the weather. In some cases, the damage to the road could be because a tack coat was not applied when laying the new road.
When a layer of cold or hot mix concrete is placed onto a road, the surface is uniformly coated with asphalt. This is used to protect the underlying concrete. This film of asphalt is generally very thin, and over time sunlight hardens the asphalt coating making it less sticky. Water also plays a role in removing the coating. Over time, the asphalt film is basically gone and the aggregate beneath it is exposed.
At this point, if a new layer of concrete is placed over the surface of this road, there will be no asphalt film to bond a new layer of concrete to the old one.
A distributor truck sprays a layer of tack coat onto the existing concrete surface before placing the new overlay of concrete. This allows the road overlay to adhere to the surface of the underlying pavement.
Once the tack coat is applied, you have to give it enough time to cure, which is when the coating becomes tacky. This generally takes five to 10 minutes.
Tack Coat Materials
In the past, the tack coat material used was cutback asphalt. In some areas today, however, environmental agencies do not allow construction companies to use asphalt cutbacks for their tack coating material due to concerns that they contain hydrocarbons, such as kerosene. This is because hydrocarbons will evaporate back into the atmosphere.
Contact your State Department of Transportation office to see if this is a requirement in the state you live in. If you are not able to use cutback asphalt in your state, the asphalt has to be diluted with water, which is generally 50/50.
Taking time to add the extra step of adding a layer of tack coating to the road surface is well worth it, as the road will stay in good condition much longer. Contact a business, such as Lien Transportation Co, for more information.