Page 86 - HIGHWAY ENGINEERING LABORATORY_FLIP BUILDER

4.0 DETAILED PROCEDURE : CORING TEST

REFERENCE
WORK PROCESS DOCUMENT

1. General. Test the core in compression not less than 2 days
after end preparation and immersing in water. Cores with
cracked or loose caps shall not be tested. Test the core
immediately on removal from the water and whilst it is still
wet.

Mark the core sample locations before positioning the
coring equipment.

Asphalt concrete may have to be cooled before sampling
to reduce the possibility of damage to the core. If the
asphalt concrete is 25 mm or less in thickness, place a
piece of dry ice 250 mm x 250 mm x 25 mm on the selected
site for ten minutes before coring. For each additional 25
mm of asphalt concrete thickness, an additional 5 minutes
of cooling time is required.

2. Placing the core in the testing machine. Wipe the bearing
surfaces of the testing machine and of any auxiliary
platens clean and remove any water, loose sand or other
material from the ends of the core, Centre the core
carefully on the lower platen of the machine. Wherever
possible use a jig to align the specimen. Do not use any
packing other than auxiliary steel platens between the
ends of the core and the platens of the testing machine.

Position the core drill with the core barrel perpendicular to
the asphalt concrete surface at the specified sampling
location.

Turn on the core barrel cooling equipment and lower the
rotating barrel steadily with just sufficient pressure to start
cutting. When the core barrel projects through the asphalt
concrete, stop the barrel rotation and turn off the cooling
equipment. Raise the core barrel and remove the core
from the hole using core retrieval equipment.

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