scope:

This handbook contains information on materials, equipment, and procedures used to clean and seal cracks in asphalt cement concrete pavements. Crack repair problem areas are also presented. Additional information can be found in the references listed in the following paragraph. AF Records Disposition. Ensure that all records created by this handbook are maintained and disposed of IAW AFMAN 37-139, "Records Disposition Schedule."

Purpose.

The purpose of sealing cracks in asphalt concrete pavements is to protect the pavement structure from premature failure. Unsealed cracks allow water intrusion and debris retention in the crack opening. Water intrusion in the cracks penetrates into the base and subbase materials creating the potential problem of a loss of strength in these materials. The weakened pavement structure can result in load-related failures such as alligator cracking (Figure 2.1.). The debris retention can cause the pavement to "push up" at the edges of the crack when the pavement expands due to thermal changes. This decreases the rideability of the pavement surface. These failures and deficiencies increase the life-cycle cost of the pavements by requiring increased maintenance.