ITEM 409 SAWING AND SEALING ASPHALT CONCRETE PAVEMENT JOINTS
409.01
Description
409.02
Materials
409.03
Construction Details
409.04 Method
of Measurement
409.05 Basis of
Payment
409.01 Description. This work consists of saw
cutting and sealing the finished surface of the asphalt concrete pavement and
shoulders directly over and in line with transverse joints in the underlying
Portland cement concrete pavement.
409.02 Materials. Use joint sealant conforming to 705.04 and approved by the Laboratory before
shipment to the project. Use a 1/2 inch (13mm) diameter closed cell foam
backer rod that will form and maintain a reservoir of sealant as specified in 409.03.
409.03 Construction Details. Saw cut,
clean, and seal transverse joints as a continuous operation. If the
surface course is not placed within 5 days after the intermediate course is
placed, make a 1/8-inch (3 mm) wide saw cut that is one-fourth the depth of the
intermediate course over contraction joints and a 1/2-inch (13 mm) wide cut
that is one-fourth the depth of the intermediate course expansion joints.
Saw
joints in the surface course as soon as the saw can be operated without
damaging the asphalt concrete, but no later than 48 hours after the asphalt
concrete is placed.
Locate
the sawed joints directly over each existing transverse pavement joint,
including joints at full-depth pavement repairs. Accurately locate joints
with pins or stakes before paving. Pre-mark the saw cut on the new
asphalt surface with a chalk line or other acceptable method. Obtain the
Engineer's approval of the method for locating and accurately marking the
proposed saw cuts before starting any resurfacing operations.
Saw
all transverse joints and create a joint sealant reservoir according to the
following table:
Measurement |
Inch (mm) |
Saw cut depth |
2 (50) |
Backer rod diameter |
1/2 (13) |
Joint sealant reservoir |
|
Width |
3/8 (10) |
Depth |
3/4 (19) |
Recess below surface course |
1/8 (3) |
The
Contractor may make one pass to achieve the full width and depth of the saw
cut. Use either dry or wet cutting.
Clean
dry sawed joints with compressed air to remove dirt, dust, or deleterious
matter. Use an air compressor with a minimum rated capacity of 100 pounds
per square inch (689 kPa) and sufficient hose for
continuous cleaning operations.
Clean
wet sawed joints with a water blast to remove sawing slurry, dirt, or
deleterious matter. Dry wet sawed joints with a propane torch or lance
unit capable of producing a blast of hot air at 2000 °F (1093 °C) and with a
gas velocity of 2000 feet per second (610 m/s).
Extend
the transverse saw cut joints the full width of the asphalt over the concrete
pavement and paved shoulders.
Do
not allow traffic to knead together or damage the sawed joints before sealing.
Heat
joint sealant material in a kettle or melter
constructed as a double boiler, with the space between the inner and outer
shells filled with oil or other heat transfer medium. Provide positive
temperature control and mechanical agitation.
Heat
the material according to the manufacturer’s recommendation. Consider the
first gallon (4 L) of material that flows out of the applicator wand at the
start of the day spoil, and discard it into a container so designated.
After
cleaning, place the backer rod in the sawed joints, then immediately seal the
joints with hot-poured sealant applied through a nozzle projected into the
sawed joint, filling from the bottom up. Ensure that the seal completely
fills the joint such that after cooling, the level of the seal is not greater
than 1/8 inch (3 mm) below the pavement surface. Fill any depression in
the seal greater than 3/16 inch (5 mm) to the specified limit by adding
additional hot poured sealant. Do not overfill the joints. Take
care in the sealing of the joints so that the final appearance will present a
neat line.
409.04 Method of Measurement. The
Department will measure Sawing and Sealing Asphalt Concrete Pavement Joints by
the number of feet (meters) of joints sawed and sealed.
409.05 Basis of Payment. The Department
will not pay for saw cuts in the intermediate course.
The
Department will pay for accepted quantities at the contract price as follows:
Item
Unit
Description
409
Foot
(Meter)
Sawing and Sealing Asphalt
Concrete Pavement Joints