Example Calculate Activity of soil and liquidity index

Data given

Liquid Limit (LL)=45%
Plastic Limit (PL)=18%
Clay content=24.2%(particle <2 micro meter)
moisture content is 29%

Liquid limit and plastic limit 

1. Calculating Activity of Soil

Plasticity Index = liquid limit - plastic limit

Plasticity Index = 45-18 = 27

Activity = Plasticity index/(%clay content )

= 27/24.2

=1.115

2. Calculate liquidity index

Liquidy Index= (Natural water content – Plastic limit)/(liquid limit-Plastic limit)

=(29-18)/(45-18)

=11/27

=0.407