material of ample size to protect mixture from the weather and to prevent
loss of heat. Loads that have crusts of cold, unworkable material or have
become wet will be rejected. Hauling over freshly placed material will not
be permitted.
3.6
TEST SECTION
Prior to full production, and in the presence of the Contracting Officer
Representative, the Contractor shall prepare and place a quantity of open
graded bituminous mixture and slurry grout according to the JMF. The test
section shall be a minimum of 30 meters 1OO feet long and 6 meters 20 feet
wide placed in one section and shall be of the same depth specified for the
construction of the course which it represents. The equipment used in
construction of the test section shall be the same type and weight to be
used on the remainder of the course represented by the test section. The
test section shall meet the requirements specified in paragraph
ACCEPTABILITY OF WORK. If the test section should fail to meet these
requirements, the necessary adjustments to the mix design, plant operation,
and/or construction procedures shall be made. Additional test sections, as
required, shall be constructed and evaluated for conformance to the
specifications at the Contractor's expense. A representative for the resin
manufacturer shall be on site during the test section construction and
during the initial placement.
3.7
SURFACE PREPARATION OF UNDERLYING COURSE
Prior to placing of open graded bituminous mixture, the underlying course
shall be cleaned of all foreign or objectionable matter with power brooms
and hand brooms.
3.8
TACK COATING
Immediately before placing open-graded asphalt mix, contact surfaces of
previously constructed pavement shall be sprayed with a coat of bituminous
material as specified in Section 02748A BITUMINOUS AND PRIME TACK COAT.
3.9
PLACING OPEN GRADED BITUMINOUS MIXTURE
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NOTE: The amount of rolling required to achieve the
required voids total mix criteria is usually 1 to 3
passes of the 1.8 metric ton (2-ton) tandem steel
wheel roller in the static mode. The appropriate
temperature of the freshly placed bituminous mixture
required to prevent undue shoving and cutting from
the roller is usually in the 50 to 70 degrees C (120
to 160 degrees F) range. The actual number of
required passes and temperature range for rolling
should be determined during construction and
subsequent evaluation of the test section.
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The mix shall be placed at a temperature of not less than 80 degrees C 175
degrees F. Upon arrival, the mixture shall be spread to the full width
(minimum 3 meters 10 feet) by a bituminous paver. It shall be struck off
in a uniform layer to a depth that, when the work is completed, will
produce the required thickness indicated. The speed of the paver shall be
regulated to eliminate pulling and tearing of the bituminous mat. Unless
otherwise directed, placement of the mixture shall begin along the center
SECTION 02746
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