What type of soil passes the No. 40 sieve and is retained on the No. 200 sieve?

The soil that passes through the No. 40 sieve and is retained on the No. 200 sieve is classified as fine sand. The No. 40 sieve has openings that correspond to a specific mesh size, allowing finer particles to pass through while catching larger ones. Fine sand typically consists of particles that are too small to be retained by the No. 40 sieve but are still larger than those that would pass through the No. 200 sieve. This specific retention and passing characteristic is critical in understanding soil classification and behavior in various engineering and construction applications.

Fine sand's unique particle size provides it with particular physical properties that impact drainage, compaction, and stability when used in earthworks and construction projects. Knowing the classification of soil based on sieve analysis helps engineers and surveyors make informed decisions regarding site preparation, foundation design, and material selection.

In contrast, soil types like clay, coarse gravel, and organic soil have distinctly different particle size distributions that do not fit the criteria described for passing the No. 40 sieve while being retained on the No. 200 sieve. Clay particles are much smaller and would pass both sieves, coarse gravel contains much larger particles that would not pass the No. 40 sieve at all, and organic soil