Base: is critical to the life of
asphalt work. It determines the solidity,
shape and drainage of the project. The
sub-base should be shaped and compacted
while removing all vegetation. Base material
is then added using the proper amount of
moisture for optimum compaction and rolled
to compact. The same process is used on an
existing project that has some base material
already in place to consolidate the surface
and provide the proper thickness of base for
the application. It is necessary to let it
dry before applying prime oil for a bonding
surface for asphalt. The drying process
could be overnight or several days depending
on the weather conditions at the time.
Essentially the same base work should be
performed for both a hot mix surface and a
chip and seal surface
Hot
Mix:
Hot mix: The mix is produced at our
plant on Highway 248 and delivered to the
jobsite by dump truck at approximately 320
degrees. The mix is dumped into the laydown
machine, which spreads and partially
compacts the material over the prepared
base. Areas that can't be reached by machine
are done by hand and all seams are raked and
consolidated by hand. As the mix cools it is
rolled for final compaction. Thickness may
vary but a minimum of 2" is required for
light duty applications.
Chip and Seal:
Chip and seal:
This type of
surface consists of applying hot asphalt oil
to the prepared surface and spreading chips
(gravel) on the oil before it cools. The
roller follows this process to compact the
chips into the oil so that it will hold them
in place. A double seal adds another layer
of oil and chips over the first one. A
double seal will amount to about 5/8" of
thickness.
Asphalt overlay:
Asphalt overlay: This requires
that any
failure areas
be repaired and
the surface to
be broomed or
cleaned to
provide a good
bonding
surface. Next a tack
oil is applied
to enhance the
bonding
characteristics
of the surface.
The hot mix is
delivered as
above and laid
over the
existing
surface and
compacted.
Post
Paving
Instructions:
Don't park a heavy object on fresh mix while
it is still hot. It could cause deflection
of the mix and leave small indentations in
the fresh mix. Fresh mix (hot) may scuff up
if you are stationary and tum your power
steering. This will not ruin the mix but
will show in the surface. We do not
recommend putting a sealer on a new asphalt
project for a few months to be sure all of
the volatiles in the asphalt have had time
to dissipate into the air. Avoid driving off
the edges of a new surface particularly with
a heavy vehicle. This puts excess weight on
a small area and may result in deflection.
REPAIRS
Existing
Projects
Existing projects can be repaired by
excavation of failure areas or just by
filling potholes.
Excavation of failure areas requires
removing the soft or failed material and
replacing it with a more stable material.
Each area is different however 18" of
excavation is not uncommon in this area. It
is then filled with a larger rock and base
to bring back to the original base level and
the surface is then added to bring it level
with the surface being matched.
Premix or cold mix is used to fill potholes
or failure areas that have occurred in the
surface. A lighter oil is used to mix it and
it can be used cold or for a longer period
of time. Holes should be cleaned of all
unconsolidated material and sprayed with oil
to provide a bonding surface. The mix is
then added and rolled to compact in place.
