specimens may be molded at several moisture contents. Therefore, compaction
procedures were developed for three moisture contents. We were unable to split
the coarse gravelly (A-1-a) material into the individual rings. The material had
very little fines and there was no cohesion to hold the material in the individual
rings. For this material, the density was determined from the total weight of the
specimen. Table A1 shows the target and obtained dry densities, moisture con-
tents, and the coefficient of variation of the densities and moisture contents.
To obtain uniform densities, the following number of tamps and kneading pres-
sure were used as shown in Table A2. Layer 1 is at the bottom of the mold. Note
that for the A-2-4 and the A-1-b soils, higher kneading pressures on the first layer
were needed 150 and 125 psi (1034 and 862 kPa, respectively). For the remaining
layers of A-2-4, the kneading pressure was decreased to 125 psi (862 kPa), with the
same number of tamps used.
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