Particle size distribution
Particle size distribution is Representation of sieving result, it helps to easy understanding the various particle size minority and the majority. For proper Understanding of particle size distribution, it is important to visualize the sieving process,
Now we know, When the Sieving is done, Different type of particles settled in their respective sieve according to their size, After that Computation of percentage finer is done,
Which help to find Percentage Finer (N), this Percentage Finer give the exact Percentage of material Retains according to sieve type,
again we can say, Particle size distribution is Representation of these result, it helps to easy understanding the various particle size minority and the majority.
Because the course grain soil property depends on particle size, particle size distribution is very useful for coarse-grained soil.
for better of particle size distribution it is important to discuss Percentage finer (N)
Percentage finer (N)
Let suppose soil is sieving. and mass of sample retained in the sieve set. giving name M1, M2……. now
percentage retains (P) could be found by dividing mass M1(mass of retaining soil in sieve 1) to total mass M,
finding percentage retain (P) for all sieve by same formula = M1 / M after that
Now cumulative Percentage (C) find =C1, C2, C3…..
for 1st number sieve {C1=P1} for second number sieve {C2 = P1+P2} also same procedure for next sieve.
lets finally find Percentage Finer (N) = For sieve number 1 (N1 = 100 – C1) for second number (N2 = 100 – C2) and the same procedure for remaining.
Particle size distribution Curve
Particle size distribution Curve is Basically graphical representation from the Data, which is collected from sieving result also from percentage finer,
we know permeability of soil depending upon the size of the particle so a guess of permeability can be found from the particle size distribution curve.
Grading of soil can be Determine with the help of Particle size distribution curve if the curve value finishes within a lower range size particle the soil called Fine graded.
If the curve starts after some skipping small particle size and between the large size particle the soil called coarse graded.
also according to curve shape we find the soil is well graded, gap graded, or uninformed graded.