15 March 2001
PARTIAL-DEPTH REPAIR OF PAVEMENTS
5.1. Purpose. The purpose of partial-depth repairs is to correct localized areas of concrete
pavement distress. Repair of this type restores rideability, deters further deterioration, reduces
foreign object damage potential, and provides proper edges so that joints can be effectively
5.2. Need for Partial-Depth Repair. Partial-depth repair is typically used to repair spalling either
at pavement joints (Figure 5.1.) or at midslab locations. Spalling can occur when unsealed joints
or cracks are filled with incompressible materials that prevent movement of the slab in hot
weather and result in breakage of the concrete. Other causes of spalling at joints include:
keyway failures (of oversized, poorly designed keyways), poor construction, poor repairs, dowel
bar lockup, improperly located dowels, and dowels in reamed-out sockets. Spalling at midslab is
generally caused by reinforcement that is too close to the surface, or foreign matter, or poor
surface finish, in the original PCC. Spalls create a rough ride and can accelerate deterioration.
Spalling is typically a localized distress and, therefore, warrants a localized repair. If several
severe spalls are present on one joint, it may be more economical to place a full-depth repair
along the entire joint than to repair individual spalls (Figure 5.2.).
5.3. Selection of Repair Boundaries. Prior
areas of unsound or delaminated concrete should be made to establish the repair boundaries.
During the survey, all areas of unsound concrete or delamination should be determined by using
a sounding technique. Sounding the pavement to find delamination and spall removal areas is
accomplished by striking the existing concrete surface with a steel rod or carpenters hammer.
Delaminated or unsound concrete will produce a dull or hollow thud, while sound concrete will