The value of group index of a soil varies from:

Question

Question

This question was previously asked in

JKSSB JE Civil Jal Shakti 6 Dec 2022 Official Paper (Shift 2)

Answer 1

Explanation:

The higher the value of the group index, the poorer the soil as a subgrade material.

Type of subgrade soil	Group index range of subgrade
Good	0 – 1
Fair	2 – 4
Poor	5 – 9
Very poor	10 – 20

∴ The range of the Group Index of soil is from 0-20

Additional Information

The group index of soil is given by

G.I = 0.2 a + 0.005 ac + 0.01 bd

a = It is the portion of % passing through 75 μ sieve greater than 35 but not exceeding 75 expressed as whole number in between [0-40].

b = It is the portion of % passing through 75 μ sieve greater than 15 but not exceeding 55 expressed as whole number in between [0-40].

c = It is the portion of the numerical liquid limit greater than 40 but not exceeding 60 expressed as whole number in between [0-20].

d = It is the portion of the numerical plasticity index greater than to 10 but not exceeding 30 expressed as whole number in between [0-20].