Describe the process by which a A bag of soil is separated i

Describe the process by which a) A bag of soil is separated into the fine-grained and course-grained fractions b) A determination is made as to whether the overall soil sample is to be considered fine-grained or coarse- grained

Solution

(a) The bag of soil can be separated into the fine-grained and coarse-grained fractions by sieving.. The soil is placed over a no. 200 (74 microns sieve mesh size) sieve and shaken vigorously. The soil which goes through the mesh of the sieve is the fine-grained fraction whereas the soil which is retained on the sieve is the coarse-grained fraction.

(b) The soil as a whole can be determined as coarse-grained or fine-grained by a similar method as in (a). If 50% or less of the soil goes through the No. 200 sieve then it is termed as fine-grained soil. If 50% or more of the soil is retained on the sieve, then it will be termed as coarse grained soil.