Define plasticity index and classify soil on its basis.

1 Answer

Answer :

a) Plasticity index (Ip) It is give measure of degree of plasticity of soil. It is difference be liquid limit and plastic limit

Ip = WL - Wp

Greater plasticity index, the greater is degree of plasticity of the soil.

[Definition in other word as “The range of moisture content over which the soil is in the plastic state is called the plasticity index”] 

b) Classification of soil based on Ip

i) Non plastic soil

 If wp = o        Ip = wL

ii) Plastic soil

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