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9.3 Heat or cool the asphalt concrete mixture to the described compaction<br />
temperature.<br />
9.4 Compact the asphalt concrete mixture in accordance with T247. Compact a<br />
sufficient amount of material to ensure that the final compacted test specimen is 102 ___4 mm<br />
in height.<br />
9.5 Determine the air void of the specimen.<br />
NOTE2.--It is not recommended that the Marshall method of compaction (AASHTO T245-82 or ASTM<br />
D 1559-89) be used. If specimens are cored from the field or from a slab, the top and bottom of the specimen must<br />
not sustain a cut surface.<br />
9.6 Measure the diameter and height or thickness of the specimen at three locations,<br />
at approximately one-third points and record the average measurement as the diameter and<br />
thickness of the specimen + 1.0 mm in accordance with D 3549.<br />
9.7 Place the specimen inside the 150-mm long rubber membrane, centering the<br />
specimen within the membrane so that there is a 25-mm overlap at each end. Inject a<br />
continuous line of silicone cement between the membrane and the specimen with a caulking<br />
gun. Use a spatula to smooth the silicone to a thick, uniform layer between the rubber<br />
membrane and the specimen. Allow the specimen to stand at room temperature, overnight or<br />
longer, until the silicone is dry.<br />
10. PROCEDURE<br />
10.1 Specimen Setup<br />
10.1.1 Place a perforated Teflon disk on top of the grooved surface of the bottom<br />
end platen inside the load frame.<br />
10.1.2 Place the specimen vertically on top of the Teflon disk and bottom end platen.<br />
NoTE 3.--For cores removed from field pavements, it is important that the specimen be placed such that the<br />
top of the specimen corresponds to the top of the pavement.<br />
10.1.3 Place a perforated Teflon disk on top of the specimen and place the top end<br />
platen on top of the disk, with the grooved surface facing the disk and specimen.<br />
10.1.4 Seal the rubber membrane around the specimen platen assembly by placing an<br />
O-ring in each groove of the end platens, over the rubber membrane.<br />
10.1.5 To ensure that the system is airtight, select vacuum with the water-vacuum-air<br />
valve. This closes the system to air and water. Open the vacuum valve until the inlet and<br />
outlet pressure reads 510 mm of Hg. Adjust the vacuum level with the vacuum regulator.<br />
Close the vacuum valve. Close the bypass valve so that the vacuum is drawn through the<br />
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