Although little distinction has been made in the past between crack sealing and crack filling, the purposes and functions of each must be clearly understood so that the most cost-effective and long-lasting treatment is applied.
Crack Sealing— The placement of specialized treatment materials above or into working cracks using unique configurations to prevent the intrusion of water and incompressibles into the crack. Crack Filling— The placement of ordinary treatment materials into non-working cracks to substantially reduce infiltration of water and to reinforce the adjacent pavement. As these definitions indicate, the objectives of crack sealing are significantly more difficult to accomplish than those of crack filling. Sealing requires considerably more forethought, greater costs, and the use of more specially formulated materials and more sophisticated equipment.
It is assumed in this manual that where cracks are exhibiting significant vertical deflections, the appropriate repair strategy will be sought. Hence, for cracks with limited vertical movement, horizontal movement becomes the critical factor in determining the need for, and planning of, a crack treatment operation.
