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

Cleaning & drying
Because dust and water will adversely affect the
adhesion of crack repair materials, this is one of
the most important steps.
Airblasting with a backpack unit or air compressor
will remove dust, debris, and some loose asphalt
concrete pieces, but is not effective at removing
surface moisture. If a moisture and oil filter is not
properly installed, airblasting can actually
introduce contaminants to the face of the crack.
This is especially problematic when sealing.
An alternative is to use a heat lance (Figure 22).
This device removes dust and surface moisture.
The heat from the lance can also help improve the
bond of the crack repair, if the material installation
follows closely behind the lance.
Other cleaning methods include sandblasting and
wire brushing. Depending upon the surface
conditions, these methods may improve the
quality of the crack repair.
Crack repairs should never be done in rainy
weather. Even the best heat lance cannot deal with
the excess moisture.
Material installation
The method of installation depends on the material
to be placed. Emulsions can be applied with hand
held pour pots. Distributor wands with hoses are
often used to place material in the crack. Figure 23
shows basic wand application of crack sealer.
In most cases, the materials need to be heated.
The temperatures can be as high as 425°F. Safety
around, and with, the crack material is a primary
concern. Crews must be trained to properly heat
and place the material.
Figure 22 – Heat lance
6 - Crack Repairs
Figure 23 – Basic wand application of
crack sealer
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