What are the factors on which Relative compactions depends ?

Relative compaction in field depends on following factors:-

1. Moisture content .
2. Geomaterial type{Nature of the soil to be compacted i.e, Sand,clay or other }
3. Compaction method such as static pressure, kneading, vibration, impact.
4. Compactive effort including applied energy, compactor size, lift thickness, number of passes.
5. Relative layer stiffness (i.e. upper layer over lower layer)