Two soils were tested for their consistency limits in the laboratory. The following data were obtained

enter image description here

plasticity of soil • 295  views

From fig the flow curves for soil A and soil B

From the fig $(w_{L})_{A}$=38%


a) $(Ip)_{A}$=38-25=13


soil B has a higher degree of plasticity soils with $IP \gt 17$ are highly plastic and soils with Ip between 7 and 17 are "medium plastic", according to one empirical classification system

b) $(IL)_{A}$=$\frac{W_{N}-W_{P}}{IP}$ = $\frac{40-25}{13}$


soil A with $I_{2}\gt 1$ is in the liquid state of consistency and will, therefore 'flow' like a viscous clurry upon remoulding. soil B with $I_{2}$=0.67 is in the plastic state and will be a better foundation material upon remoulding.

c)soil with WL=60% is more compressible than soil A with wL=38% compressibility is a direct function of the liquid limit

d) From fig, Flow Index, If of soil A=42.0-32.0=10 (Considering water content at 10 and 100 blows) If for soil B=6.26-55.5=71

Since $(IF)/A \gt (If)_{B}$ soil A showed greater loss if shear strength with increase in water content

e) Toughness Index, $I_{t}$ for soil A=$\frac{IP}{IF}=\frac{13}{10}$=1.3

If for soil B=$\frac{Ip}{If}=\frac{30}{71}$=4.22

soil B has a higher shear strength at plastic limit since a soil with higher toughness index possess higher shear strength at plastic limit

Please log in to add an answer.

Continue reading

Find answer to specific questions by searching them here. It's the best way to discover useful content.

Find more