Whether routing is used or not the crack must be cleaned before material is introduced. Compressed air should be used to blow out debris and any loose particles. Cracks should then be sealed with a crackseal material (hot- or cold-applied) and banded by “V”-shaped squeegee after application. A hand squeegee or a stationary foot on the pour pot can be used to band the crackseal material on either side of the crack. This banding completes the cracksealing process and aids in sealing water from entering the crack.
Crackseal is a preventive maintenance application to seal cracks with a surface opening of ¼ inch or more. Cracksealing is applied into the crack after it has been cleaned of all sand, dirt, debris and all non compressible materials. Also, the crack must be dry and free of moisture prior to applying the sealant.
The cracksealing material can be either cold poured or hot poured. Hot-poured sealant is applied to the cracks from pour pots or from an on site hot pot, through a hose and wand applicator under pressure. Cold-poured sealant is applied by pour pot only. Material applied with the wand and under pressure is designed to penetrate into the crack; this is an excellent way to apply the cracksealing material. However, the tip of the wand must be placed at the entry of the crack in order to be applied correctly and to get the maximum benefit of the application.
It is not recommended or acceptable for the material to be “shot” at the crack opening from a distance because the material will not have the proper, recommended and specified flow entry. Also, “shooting” material creates a messy application and increases the cost.
Pour pot application is a gravity installation meaning the material gets the penetration needed from gravity flow and from the pressure applied to the pour pot by the operator. Pour pot application is an acceptable method of sealing cracks. However, the pour pot must have the proper application foot that is in contact with the surface, forcing material into the crack and banding the material to both sides of the crack. The cracksealant must be banded or spread on the pavement next to the crack and cover a width of 13 inch to 1 inch on both sides of the crack.
Excerpted from Guide to Pavement Maintenance by Thomas McDonald and Patrick McDonald, Pavement Maintenance Information Source, 18521 E. Queen Creek Road, Suite 105-435, Queen Creek, AZ 85242; www.pavementmaint.com. For information on the book e-mail them at firstname.lastname@example.org.