UFC 3-270-02
15 March 2001
CHAPTER 10
PROBLEM AREAS
10.1. Categories of Problems. Many problems that arise during a sealing project can be
divided into three categories--crack sealant materials, crack preparation, and crack sealant
application. The following information is presented for these three sealing problems.
10.1.1. Materials. One of the main problems associated with the sealant materials is
nonconformance to the required specification. This problem can be minimized by having the
sealant tested by an independent laboratory. Another problem is a combination between
materials and application which involves the sealant not setting up or curing once it has been
applied to the crack. This problem is often caused by overheating the sealant before it is applied
to the crack. The overheating can be caused by heating the sealant at too high a temperature or
heating it at the recommended pouring temperature for an extended period of time. Most
sealants used to seal cracks in asphalt concrete pavements are asphalt cement based materials,
and overheating causes the light volatiles to "cook off" or evaporate. This causes the sealant to
become brittle, resulting in premature failure of the sealant. This problem can be solved by
monitoring the temperature of the sealant in the application equipment and discarding any
material that has been heated for longer than 4 hours. It is also recommended that the sealant
remaining in the equipment be discarded and the equipment thoroughly cleaned after each day's
work has been completed.
10.1.2. Preparation. The main problem associated with crack preparation is the cleanliness of
the crack. The crack sealant will not adequately bond to the pavement if there is dust, debris, or
loose aggregate remaining in the crack. Damaging the pavement during the routing process can
also be a problem. Care must be taken by the equipment operator so that each crack is followed
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