From this data from seiving a sample of coarse grained soil , What can we conculde from this data? What is Sand and gravel in this data andwhat  can be something intersting from this data?

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jeew-m | College Teacher | (Level 1) Educator Emeritus

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This questionn is related to soil classification using sieve analysis in the area of soil mechanics. First we have to know some basics of soil mechanics to move further.

Coarse grained soil

If more than 50% of the weight of sample retained on No. 200 sieve (0.075mm) then we called that soil is a coarse grained soil.

Fine Grained soil

If more than 50% weight of the sample passes through No. 200 sieve we call it a fine grained soil.

According your table 99.3% of the weight is retained on 0.075mm sieve. That means this soil sample is a coarse grained soil sample.

Coarse grained soils are divided in to further two categories as gravel and sand.

If more than half of the coarse fraction retain on No.4 sieve (4.75mm) we call it gravel.

If more than half of the coarse fraction passes through No.4 sieve (4.75mm) we call it sand.

According to the table only 0.02% of the total weight is retained on No.4 sieve. This means the soil sample is a sand.

If we consider the gradation of the soil sample it is a poorly graded soil samples. The sample is rich with 0.3mm and 0.15mm size particles. other particle sizes are very low.

So finally we have poorly graded coarse grained sandy soil. It falls in to SP soil category.