Procedure

Measure the dimensions of each cut specimen: take two diameter and two thickness measurements with a precision of 0.1 mm.

•	1. In the drying chamber, weigh each cut specimen in water using the balance and setup illustrated in Figure 11.8.

•	2. Dry the surfaces of each specimen with clean, dry tissue and weigh it in air using the balance in the drying chamber.

•	3. Apply tapes to both flat surfaces and dry the curved surface further with air pressure.

•	4. Coat the curved surface of each specimen with melted wax (Figure 11.10).

•	5. Once the wax coating has cooled to room temperature and hardened, remove the protective tapes to expose the flat surfaces having the same diameter as the specimen (Figure 11.10).

•	6. Transfer the wax-coated specimens to the drying chamber. Weigh each wax-coated specimen in air using the above-described balance (to obtain initial weights for the drying test), then mount them on the support in the chamber for drying (Figure 11.11).

•	7. Weigh each specimen according to the schedule below:

Day 1: 3 measurements at 0-, 1- and 6-hour intervals.

Day 2 to Day 7: one measurement every 24 hours.

Day 8 and later: three measurements per week.

•	8. Stop weighing when the 10-mm thick specimen reaches equilibrium mass change: five successive mass change determinations are constant within ±0.005% of specimen mean value. At this point, stop testing on all specimens.

Figure 11.10 – Wax-coated curved surface of the test specimen.
(cutaway view on the left, top view on the right)

Figure 11.11 – Wax-coated specimen in the uniaxial drying test.
(cutaway view)