UFC 3-250-03
15 May 2001
mixer, mix the aggregate (and stabilizer) and asphalt cement quickly until the aggregate is thoroughly
coated.
[2] Plant produced samples. For plant produced samples, duplicate samples should
be tested at the plant production temperature. Samples may be obtained during plant production by
sampling the mixture at the trucks prior to the mixture leaving the plant. Samples obtained during actual
production should be reduced to the proper test sample size by the quartering method.
(e) Procedure. The following procedure can be used for both laboratory and plant
produced SMA mixtures.
[1] Transfer the uncompacted SMA mixture sample to a tared wire basket described
in figure 2-17. Place the entire sample in the wire basket. Do not consolidate or otherwise disturb the
sample after transfer to the basket. Determine the mass of the sample to the nearest 0.1 gram.
[2] Determine the record the mass of a paper plate to the nearest 0.1 gram. Place
the basket on the paper plate the place the assembly into the oven at the temperature as determined in
paragraph [3] for 1 hour 1 minute.
[3] After the sample has been in the oven for 1 hour, remove the basket and paper
plate. Determine and record the mass of the paper plate to the nearest 0.1 gram.
(f) Calculations. Calculate the percent of mixture which drained by subtracting the initial
paper plate mass from the final paper plate mass and divide this by the initial total sample mass.
Multiply the result by 100 to obtain a percentage.
(g) Report. Report the average percent drainage at the test temperature.
(2) Job-mix formula requirements. It is the contractor's responsibility to ensure that, in addition
to the aggregate gradation requirements, the produced material will provide an asphalt mixture that
conforms to the applicable design parameters listed in table 2-16. The contractor shall submit in writing
the proposed job-mix formula (JMF) for approval including the following:
(a) The percentage (in units of 1 percent) of aggregate passing each specified sieve
(except the 75Fm (No. 200) sieve), based on the total dry weight of aggregate as determined by ASTM
C-117 and C-136.
(b) The percentage (in units of 1/10th of 1 percent) of aggregate passing the 75 Fm
(No. 200) sieve, based on the dry weight of aggregate as determined by ASTM C-117.
(c) The percentage (in units of 1/10th of 1 percent) of aggregate finer than
0.020 millimeter in size, based on the dry weight of aggregate as determined by ASTM D 422.
(d) The percentage (in units of 1/10th of 1 percent) of asphalt material to be added, based
upon the total weight of mixture.
(e) The proposed percentage of each stockpile to be used, the average gradation of each
stockpile, and the proposed target value for each sieve size. The target values and the combined
average gradation of all the stockpiles when combined in accordance with the contractor's
recommended stockpile combinations shall be within the gradation ranges for the designated grading in
table D1.
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