AS NZS 2891.7.1:2015 pdf free
AS NZS 2891.7.1:2015 pdf free.Methods of sampling and testing asphalt Method 7.1: Determination of maximum density of asphalt- Water displacement method
The following apparatus is required:
(a) Pycnometer for on balance method A flat bottomed thick-walled flask, able to withstand a vacuum of -90 kPa gauge pressure or lower, of about 2 L capacity; the top of the mouth of the pycnometer shall be ground flat. The flask shall either have a side arm for attachment of the vacuum line or be fitted with a rubber stopper with provision for a vacum tube.
(b) Pycnometer lid A glass plate slightly larger than the top of the pycnometer and ground flat on one or both sides.
(c) Flask for under balance method A flat bottomed thick-walled flask or vacuum pot of plastic or alloy, with transparent cover of sufficient capacity to allow vacuum evacuation of the specimen fully immersed in water with rubber seal and a connection for vacuum. The flask shall be capable of withstanding a vacum of -90 kPa gauge pressure or lower.
NOTE: Suitable forms of vacum flasks and pycnometers of alloy and heavy gauge plastic are available commercially for determination of maximum density of asphalt using the methods given in this Standard.
(d) Water/vapour trap Fitted in line before the vacuum pump to prevent the transfer of water and water vapour to the vacuum pump.
(e) Vacuum system Comprising a vacuum pump capable of maintaining a vacuum of -90 kPa gauge pressure or lower in the pycnometer or flask, tubing and an inline device for measuring the vacuum such as a vacum gauge.
NOTE: The inline device for measurement of the vacuum should be fitted using a ‘T’piece type connector and should be located towards the end of the vacuum line near the pycnometer or flask.
(f) Water bath The bath shall have a means of maintaining a constant temperature: of 25 ±1°C or within 1°C of an alternative test temperature. The bath should be emptied and cleaned at regular intervals to ensure that the water in the bath is clean and not contaminated. For the on balance method, the bath shall be filled with clean water and have sufficient capacity to contain the immersed body of the pyconometer. For theunder balance method, the bath shall be fitted with an overflow and filled with clean water to the level of the overflow at all times. The dimensions of the bath shall be such that the fully immersed flask shall be at least 50 mm from the sides and bottom of the bath.AS NZS 2891.7.1 pdf free.
