AS NZS 2891.5:2015 – Methods of sampling and testing asphalt Method 5: Compaction of asphalt by Marshall method and determination of stability and flow—Marshall procedure
AS NZS 2891.5:2015 – Methods of sampling and testing asphalt Method 5: Compaction of asphalt by Marshall method and determination of stability and flow—Marshall procedure.
(b) If required, prepare a sample of asphalt in the laboratory in accordance with
(c) Remove the specimen mould assembly from the oven and place a paper disc in the bottom of the mould.
td) Obtain a rcprcsentatñc test portion of the asphalt of sufficient mass to obtain a compacted specimen height of approximately 63.5 mm but within the allowable range of 57 mm to 70 mm. Place the test porlion in the mould and spade the asphalt with a heated spatula 15 times around the perimeter and 10 times over thc interior.
SOIl: The epccted hulk density of the compacted asphalt may be used to calculate the mass necessary to gic the desired specinien height.
(c) Place the mould in the oven for sufficient time for the test portion to reach the specified compaction temperature. If the test portion has not reached the specified temperature within 60 minutes discard the test portion.
6.2 Plant produced mix
Plant produced mix shall he prepared as follows;
(a) Unless otherwise specified, obtain a hulk sample of asphalt in accordance with
(b) Preheat the specimen mould assembly in the oven,
(c) Obtain a representatie test portion of’ the asphalt of sullicient mass to obtain a compacted specimen height of approximately 63,5 mm but within the allowable range of 57 mm to 70 mm by either
sample division of freshly produced asphalt that is at a temperature to facilitate sample division or
(ii) placing a sample container in an oven, at a temperature not exceeding l60C to reheat the sample. The sample shall not be in the oven for more than 3 h in total. When the sample is at a temperature to t’aciliate sample division remoe the sample container from the oven and transfer the sample to a mixing tray or bowl and prepare test portions.
SOTI:: The expected bulk density of the compacted asphalt may be used to calculate the mass necessary to give the desired specimen height.
idt Place the test portion in the mould and spade the asphalt with a heated spatula IS times around the perimeter and 10 times over the interior.
(e) Place the mould in the overt for sufficient time for the test portion to reach the specified compaction temperature. If the test portion has not reached the specified temperature within 60 mm discard the test portion.
7 COMPACTION OF SPECI%IF.NS
The compaction procedure shall be as follows:
(a) Remove the mould from the oven. Place a thermometer in the mould and verify that the temperature of the asphalt in the mould is within the tolerance for the compaction temperature specified in Tables I, 2 or 3. Record the temperature.
(b) Place a circular paper disc on top of the asphalt and transfer the mould assembly to the compaction pedestal,
(c) At a rate of 60 to 70 blows per minute. compact the mix using the specified number of blows of the compaction hammer with the hammer axis held vertically. Insert the mould and apply the same number of blows to the other end of the specimen.
I Where the number of b[ows is not pcci1ied. 50 blows is commonly used.
2 Some laboratories that usc dual head automatic hammers insert and sap the tso moulds such that each mould receises the %ame compaction energy oseragcd between two hammers.
3 Whcre hand compaction is used the sliding mass of the compaction hammer houId be raiscd to its highest position without lifting the face of the hammer trom ihc surface of the asphalt. Immediately after the sliding mass has reached the bottom of its free fall it should be caught such that it does not bounce on to the specimen creating additional compactise effort.
(d) Repeat Steps (a) to (e) to produce a minimum of two specimens, these operations being Continuous to minimize heat loss.
(c) Retain the specimens in the nioulds and remove the paper discs from their faces. Mark the top of each specimen with an identification number.
(I) Remove the specimens from the moulds using the specimen extraction equipment and allow the specimen to cool.
NOTE: Care should be taken to ensure that the specimen has cooled sufliciently to ensure that it does not deform sshen removed from the mould.