Inspection of the existing pavement will indicate where problem
areas are likely to occur. Existing signs of slipping should be
isolated and repaired. If the surface of the existing pavement
has the presence of oil and grease from traffic or a prior seal
coat, the tack is not likely to adhere correctly and a slip is
often the result. If the existing pavement in a high-stress area
is polished and has a fine textured finish, it may be necessary
to scratch the surface with a milling machine to allow for a
mechanical connection between the layers, in addition to the
adhesion bond. This technique is becoming more prevalent because
it ensures a textured surface for the overlay to bite to and
simplifies the complications of the tacking process.
Thermoplastic "stop bars" should be milled off prior to
overlaying. To repair a slipped pavement it is necessary to saw
cut and remove the old pavement. The limits of the sawed area
must be outside the distorted area, so that a good seam to sound
pavement is possible. The asp