AS NZS 2891.7.1:2015 pdf free download – Methods of sampling and testing asphalt Method 7.1: Determination of maximum density of asphalt-Water displacement method

AS NZS 2891.7.1:2015 pdf free download – Methods of sampling and testing asphalt Method 7.1: Determination of maximum density of asphalt-Water displacement method.
The procedure to determine the volume of the pycnometcr used in Procedure 9.2 shall be as follows:
(a) Weigh the pycnomctcr and lid and record the mass (m1).
(b) Fill the pvcnometer with water from the water bath and place in the water bath.
(c) Leave the flask in the water bath until the water temperature in the flask and water bath are the same. Record the temperature olthe water (I,).
(d) Top up the pycnometer with water from the water bath and slide on the lid ensuring that no air bubbles are trapped.
(e) If air bubbles are ohsered repeal Steps e) and (d) until all air is eliminated.
(f) Carefully dry the outside of the pycnometer. Weigh the pycnometer. lid and water and record the mass (a,.).
(g) Empty and dry the pycnometer.
NOTE: Step ta) to Step (f) of th procedure determine the volume of the flask at thc test temperature (ii). Following an initial determination, only periodic checks need be carried out—at least six monthly.
Determine the maximum density of each test portion using Clause 9.2 or Clause 9.3. The test is intended to be undertaken at a test temperature of 25°C however, where the test is undertaken at an alternative test temperature. any prior determinations of the volume of a pycnomcter or mass of a flask shall he completed at the same temperature as that in Clause 9,2 or Clause 9,3,
(e) Place the test portion into the flask and record the mass of the test portion (m,). Pour water into the flask until the water level is about 50 mm above the level of the test portion. 2 mL of detergent solution may be added to the flask to aid evacuation of air from the sample.
(1) Seal the flask and connect it to the vacuum pump and evacuate the flask to a vacuum of —90 kPa gauge pressure or lower and maintain the vacuum for a period of not less than 1 5 minutes. Vigorously agitate the flask frequently to loosen the particles and release any entrapped air.
NOTES:
1 Care should be taken when applying the vacuum particularly in the initial stages to prevent loss of material.
2 Care should be taken to ensure the sample is not left under vacuum tbr an excessive period of time as this may lead to rupture of the bitumen film and absorption of water by the aggregate. Typically 15—20 minutes of vacuum with frequent agitation is sufficient.
3 Where a glass flask is used a rubber mat below the flask during agitation is recommended.
(g) When no entrapped air is observed, release the vacuum slowly and disconnect the vacuum pump from the flask.
(h) Submerge the flask carefully into the water bath ensuring no loss of the test portion during the process and that no air is introduced into the test portion. Suspend the fully submerged flask from the balance.
(i) Record the mass of the test portion and flask in water (ms).
(j) Record the temperature of the water in the bath (Ii).