##  [Plasticity Index](/plasticity-index) 

  ##  [Plasticity Index](https://engineering.quantumdictionary.io/plasticity-index-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The numerical difference between a fine-grained soil's liquid limit (LL) and plastic limit (PL): PI = LL − PL; it quantifies the range of water contents over which the soil behaves plastically and serves as an empirical indicator of clay content, plasticity, and related engineering tendencies.