The methods of draindown testing described in this chapter differ in details. Table 8.4 shows the most important differences among them. Table 8.5 depicts commonly adopted assessment criteria of draindown testing results.
The following remarks deserve mention: [50]
Drain-Off Test Parameters for Schellenberg’s Method according to EN 12697-18
Test three samples of the same mix with the same binder content.
Test temperatures depend on the binder type:
1. For road binder—at the production temperature of a mix defined according to EN 12697-35 and raised by 25°C
2. For modified binder—at the production temperature of a mix defined by the binder supplier and raised by 15°C
• Mass of an aggregate mix sample—1000 g for a mix with the density of 2.65-2.75 g/cm3
• If the density of an aggregate mix is different from the given reference density, a sample mass should be calculated to obtain the same test material volume
60 ± 1 minutes
1. Prepare three batches of aggregate (batches 1, 2, 3) and place batch in a metal container.
2. Put the beakers in the oven at the test temperature for 15 minutes minimum; then remove them, weigh them with an accuracy of 0.1 g, and return them to the oven.
3. Mix 1 kg of a bituminous mixture at the fixed temperature according to EN 12697-35.
4. Remove the beaker for batch 1 from the oven, quickly put the prepared mix in the beaker, weigh the beaker with the mix with an accuracy of 0.1 g, write down the time and the beaker number, and return the beaker to the oven (it should not be left outside the oven for longer than 60 seconds)
5. Prepare the two remaining batches of the mix in the same way and put them in the beakers.
6. Keep each beaker with the mix in the oven for 60 ± 1 minutes.
7. Remove the first beaker with the mix, measure its temperature, and put the mix aside.
8. Remove the remaining two beakers with the mix from the oven and empty them out by tilting them upside down and holding them in that position for 10 ±1 seconds.
9. After cooling beakers No. 2 and No. 3, weigh them together with the remaining binder with an accuracy of 0.1 g.
10. If more than 0.5% of the initial mass of the mix remains on the beaker walls (including aggregate grains and mastic), the material remaining in the beaker should be washed with the solvent and passed through a 1-mm sieve; next, the material remaining on the sieve should be dried and weighed with an accuracy of 0.1 g.
11. Determine draindown as the percentage of the binder mass remaining in the beaker compared with the mass of the mix.
12. Calculate the material draindown, D, and when appropriate, the material remaining on the 1-mm sieve, R:
(W — W — W4)
(W2 — W1)
(Continued)
Drain-Off Test Parameters for Schellenberg’s Method according to EN 12697-18
W,
(W — W)
where
D = Material draindown (% m/m)
R = Material remaining on the sieve 1.0 mm (% m/m)
W1 = Mass of the empty beaker (g)
W2 = Mass of the beaker with the mix (g)
W3 = Mass of the empty beaker together with remaining mastic (g)
W4 = Mass of the dry material remaining on the 1.0-mm sieve (g)
13. The average result of two measurements should be given with an accuracy of 0.1%.
14. Results for D and R (if applicable) should be reported.
• 
None of the three beakers containing the mix may be kept in the oven for longer than 60 ± 1 minutes.
• While mixing components of the mix, pay attention to the proper sequence of their dosages, particularly fibers, polymers, and so on.
• In the case of modified binder, a lot of mastic can stick to the walls of the beaker and remain there when emptied out (due to increased tackiness of a mix). In such a case, retesting should be conducted at a temperature 5°C higher. If the new result is lower than the previous one, it should recorded in a report.
• If the difference between the test results for two samples of the same mix with the same binder content exceeds 0.5%, a new pair of samples should be tested. [51] [52]
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TABLE 8.4 A List of Differences among Methods of Draindown Testing
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assessment criteria of draindown Testing Results
drain-off Testing result, % (m/m) assessment
>0.3 Risk of binder draindown
0.2-0.3 Acceptable value
<0.2 Recommended value [53]
8.2 FILLER TESTS
8.3.1 Tests of Specific Surface with the Use of Blaine’s Method
Blaine’s method is chiefly used when testing cement (grinding gradation control). It consists of the measurement of time necessary for air to flow through a compressed layer of tested material of a given size and porosity. At standard conditions, the specific surface is directly proportional to 4t (t = time of air flow). A master sample with a known specific surface is required to calibrate testing. The test can be carried out according to EN 196-6.*
