Specifications include, but are not limited to: A. Surface Preparation: All surfaces shall be dry and free of all dirt, dust, grease,
and loose material prior to application of the mastic. All surfaces shall be
cleaned by the use of compressed air produced from an air-compressor with the
capability of producing a minimum of 125 cfm (0.06 cubic meters per second) of
clean, oil-free compressed air equipped with a maximum of a ¾ inch (20mm)
diameter nozzle. The use of “backpack” type blowers is not allowed.
In the event of surface temperatures falling below 40˚F (4˚C), a compressed air
heat lance shall be used to thoroughly dry all moisture and heat the surface
area as per the manufacturer’s recommendations. The compressed air heat
lance shall produce a minimum temperature of 750˚F (399˚C) at a minimum
velocity of 650 feet per second. The compressed air must be produced from
an air-compressor with the capability of producing a minimum of 125 cfm
(0.06 cubic meters per second) of clean, oil-free compressed air. The use of direct flame dryers will not be permitted. Caution shall be taken as to not
overheat pavement surfaces.
When recommended by the mastic manufacturer, a surface conditioner or
primer approved by the mastic manufacturer shall be applied to the surfaces
prior to placement of the asphalt repair mastic to promote increased surface
adhesion to the existing pavement. If used, the surface conditioner or primer
must thoroughly cover all surface areas where the asphalt repair mastic will
be placed. The installation of the asphalt repair mastic will not take place until
the surface conditioner or primer has cured to a “tacky” consistency.
B. Installation: The Contractor must be trained and approved by the mastic
The asphalt repair mastic shall be heated in a thermostatically controlled
mastic mixer that utilizes oil as a heat transfer medium. The Mastic mixer
must be equipped with a full sweep horizontal agitator capable of gently lifting
the material from the bottom of the reservoir and turning the material over and
over. The agitator shall be capable of mixing and suspending materials, filled
with aggregates having a specific gravity as high as 3.0.
The heated asphalt repair mastic will then be dispensed onto the properly
prepared pavement recess, in layers if needed. Immediately following, a
heated hand squeegee shall be used to level and smooth the repair mastic
with the surrounding pavement surface until the material has formed a
durable, well-bonded repair. The heated hand squeegee shall be kept free of
material buildup to ensure a smooth, quality finished product.
The asphalt repair mastic shall be applied to the applicable surface area from
the bottom up in lifts appropriate to the specific application. Due to the depths
of some of the repair locations, a minimum of two lifts may be required to
obtain a level surface. In the event that multiple lifts are required, the first
application should fill the work area to within 0.5" (12mm) to 1" (25mm) of the
desired reservoir depth. The first lift shall be properly cooled before any
subsequent lifts are applied. All excess material shall be removed from the
roadway and properly disposed of.
The Contractor shall cooperate with the Engineer to keep accurate running
totals of the pounds of mastic used.