how do you roughly classify sand into fine sand and coarse sand?

Question

aggregates

Answer 1

It's classified by size, and a size comparator is usually used to visually identify the size. You hold the comparator next to the grain and match the grain sizes.

Coarse grained sand is 1mm to 0.5mm
Medium grain sand is 0.5mm to 0.25mm
Fine grained sand is 0.25mm to 0.125mm
Very fine sand is 0.125mm to 0.0625mm

Here's a link to the full Wentworth scale, which is used to classify sediments by their size:
http://www.geoearth.uncc.edu/geopick/Courses/PG_Presentations/Sedimentary_Rocks/img006.gif

Here's a more colorful representation:
http://www.glossary.oilfield.slb.com/DisplayImage.cfm?ID=202

And one which may be easier to use.
http://www.emporia.edu/earthsci/amber/go240/sediment.htm#classify

Answer 2

A rough classification can be done with a vibrating screen. The sand is poured onto a screen with a mesh opening which will allow sand particles of a maximum particular size to pass, but will not allow larger sizes to pass. By vibrating the screen, or sifting back and forth, most of the smaller particles will have gained access to a screen opening after some amount of time, leaving essentally the larger sand particles behind. Multiple classifications can be made by sifting through progressively smaller screens.

Answer 3

Use the "Standard Specifications for Transportation Materials and Methods of Sampling and Testing".
AASHTO M145-87 Recommended Practice for the Classification of Soils and Soil-Aggregate Mixtures for Highway Construction Purposes.
It's based on a sieve system and the size and amount of material passing through. Also look for the Textural Classification chart for soils. Source: Soil Survey Staff, Bureau of Plant Industry, Soils, and Agricultural Engineering.
Soil Survey Manual - USDA Agricultural Handbook N0. 18 Washington: US Govt Printing Office.

Answer 4

The process is called "particle size analysis" or PSA. There are many methods and instrumentation to achieve it, some very complex and

For classification of sand grain distribution you could use a stack of sieves with decreasing sized openings from the top sieve to the bottom.

Answer 5

By the size of the particles.