One of the best methods of laboratory compaction is considered to be Gyratory for not only the material’s assessment of compactibility, but also the production of test samples. The method achieves this by the application of a vertical stress, typically 600 kPa via platens to a mass of asphaltic mixture inside a 100 or 150mm diameter mould. Whilst platens are kept parallel and horizontal, the longitudinal axis of the mould is gyrated at a fixed angle to the vertical axis.
During the test process, the height of the specimen is measured automatically and the mixture density and void content are calculated.
Compaction data is displayed in real time (graphical and tabular) and is available for download to MS Excel™ The operator has the ability to choose whether to compact for a certain number of gyrations or until a target mixture density or void content is achieved.