Atterberg limits test

Atterberg Limits test is performed in order to differentiate the state of the soil from the four main states of soil namely;

1) Solid
2) Semi solid
3) Plastic
4) Liquid

The test is performed using a apparatus called Cassagrande.
Testing procedure

1) Liquid limit : Water content where cut close at 25 blows.
2) Plastic limit : Water content at the point where 3mm threads start to crumble.
3) Plasticity index : LL – PL
4) Liquidity index : (w- PL) / PI

More information on soil types and classification;
AS1726,    AS 1289