Pavement Maintenance - Cornell Local Roads Program - Cornell ...

6 - Crack Repairs
_____________________________________________________________
Crack repairs are the proper and timely maintenance of cracks using sealing or filling techniques
to extend pavement life. Crack repairs are very cost effective if done properly. A crack repair
program begins by determining if crack repairs are suitable for the type of distress.
Determining Type of Maintenance
The first step is to inspect the roadway and examine the cracking. Two different factors need to
be examined: crack density and the level of edge deterioration. The width of the crack also needs
to be determined.
Crack density is a subjective term describing the spacing of the cracks. If there are only a few
cracks along the length of roadway, then the density is low. If there are cracks over the full
length of the pavement, the density is high. If you are not sure, the density is probably moderate.
Edge deterioration is a measure of the condition of the cracks. Spalling, secondary cracks,
cupping, and faulting are all examples of edge deterioration. A single transverse crack may be
low in density. A badly deteriorated single crack is still low in density, however, it is not a
candidate for crack repairs. If the edge is deteriorated too much, crack repairs will not be
successful, and patching or area repairs are needed.
Crack width is important to determine, if the repair is to be successful. If the crack width is less
than 1/4 inch (the width of a pencil eraser), then the crack is too narrow for sealing and filling. A
crack this size is not wide enough to allow the repair material to enter and function. Narrow
cracks may be surface treated. Alternatively, they can be widened by routing or sawing.
Figure 18 shows an isolated crack with a large amount of edge deterioration. The initial crack
has spawned many secondary cracks. If all the cracks were combined together, the width would
be significantly more than one inch. This is a good candidate for patching.
Figure 18 - Crack with high level of edge deterioration
Cornell Local Roads Program 33