The method of preparing SMA samples in the laboratory to determine the void content is specified in the standard EN 13108-20, Item 6.5, with details in Annex C (Table C.1). The NAD should provide values of compactive efforts. Permissible methods include the following:
• Impact compaction according to EN 12697-30, with possible energies or 2 x 25 blows, 2 x 50 blows, 2 x 75 blows, or 2 x 100 blows
• Gyratory compactor according to EN 12697-31, with different numbers of gyrations
The standard EN 13108-20 also states that the JMF should clearly state the adopted method and prevailing conditions of the sample preparation.
