Liquid Index

Liquid index, abbreviated as LI, also called liquidity index, a dimensionless number, is scaling the natural moisture content of a soil sample to the liquid limit and plastic limit.

 

Liquid Index formula

\(\large{ LI =  \frac{ PL \;-\; w_n }{ LL \;-\; PI }   }\)

Where:

Units	English	Metric
\(\large{ LI } \) = liquid index	\(\large{dimensionless}\)
\(\large{ LL } \) = liquid limit	\(\large{dimensionless}\)
\(\large{ w_n }\) = natural water content (moisture content)	\(\large{dimensionless}\)
\(\large{ PI }\) = plastic index	\(\large{dimensionless}\)