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Sieve Analysis involves passing a soil sample through sieves with successively
                      smaller  holes.  Consequently,  the  method  cannot  determine  individual

                      particle  sizes.  It  only  divides  the  particles  into  size. All  particles  retained
                      categories bracketed by the sieve opening size on a given sieve in a stack are
                      larger than the holes in that sieve but smaller than the previous sieve's holes.

                      By dividing the mass retained on each sieve by  the total mass, the percent

                      of the particles in each  size range can be determined are made  of woven

                      wire screen. They are available in many Sieves holes size from 100 mm to

                      0.037 mm. The smallest practical size is the 0.074 mm #200 sieve, since it is

                      difficult to even pass water through smaller holes. Occasionally the J1270
                      sieve (0.053 mm) is used to separate the sand from the silt fraction, but sieve
                      analysis is usually used only  to separate out sand and gravel particles. The

                      openings in sieves are square. The opening size is the square opening.


                      Since soil particles distance between two sides of some particles with longer

                      dimensions will occasionally pass through a given sized opening while others

                      with  a  shorter  dimension  may  never  become  properly  oriented  to  pass
                      through  the  sieve  analysis  data  must  be  accepted  with  this  limitation

                      opening.    Also  neither  sieve  analysis  nor  hydrometer  analysis  provides
                                                                           .
                      information about the shapes of the particle. A more serious limitation of

                      sieve analysis of soil materials is  their elemental the difficulty of separating
                      all  particles  into    grain  without  crushing  some of  the  grains.  Also,  finer

                      particles will often adhere, due to electrostatic forces, to larger particles, and

                      thuswill be measured as larger-sized particles.
                      The best method of performing sieve analysis on soils is to pulverize an air-
                      dry sample, then wash the fines through a 0200 sieve. That 1frtion of the

                      sample retained on the #200 sieve is easy to pulverize after oven drying and
                      no fine particles will remain to attach to the larger particles.





















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