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How to Do a Sand Sieve Analysis

Published in Sieve Analysis 5 mins read

Performing a sand sieve analysis is a fundamental process used to determine the particle size distribution of a sand sample.

Sieve analysis, also known as gradation testing, is a method used to assess the size distribution of granular material. For sand, this is crucial for various applications like construction, where specific aggregate sizes are required. The process involves passing a sand sample through a stack of sieves with progressively smaller mesh sizes.

Here's a step-by-step guide on how to perform a sand sieve analysis:

Materials and Equipment

  • Sand sample
  • Set of standard sieves with decreasing mesh sizes (stacked with the largest mesh on top)
  • Pan or receiver (placed at the bottom of the sieve stack)
  • Lid (for the top sieve)
  • Accurate scale or balance
  • Mechanical sieve shaker (optional but highly recommended)
  • Brush (for cleaning sieves)

Detailed Steps for Sieve Analysis

  1. Prepare the Sample:
    • Choose a sample of the material to be tested. Ensure the sample is representative of the sand you are analyzing. It should be dry.
    • Determine the required sample size based on standards or the maximum aggregate size present. For sand, a sample size of around 500-1000 grams is common.
  2. Weigh the Initial Sample:
    • Weigh the sample accurately using your scale.
    • Record the weight of the total dry sample. This initial weight is crucial for calculating the percentage retained on each sieve.
  3. Assemble the Sieve Stack:
    • Stack the sieves in order, starting with the largest mesh size at the top and placing the pan at the bottom. Place the lid on the top sieve.
  4. Add the Sample:
    • Place the sample on the top sieve of the stack. Distribute the sample evenly over the sieve surface.
  5. Shake the Sample:
    • Place the sieve stack in the mechanical shaker.
    • Turn on the mechanical sieve shaker. The shaking action helps the particles pass through the appropriate sieve openings. Shake for a sufficient duration (e.g., 10-15 minutes) according to relevant standards (like ASTM or AASHTO). Manual shaking can also be done, but it's less consistent.
  6. Weigh Retained Material:
    • Carefully remove the sieve stack from the shaker.
    • Starting from the top sieve, remove each sieve one by one.
    • For each sieve, weigh each sieve and record the weight of the materials collected in it. To find the weight of the material retained, you'll need to subtract the weight of the empty sieve from the total weight (sieve + material). Alternatively, you can zero out the scale with the empty sieve on it before adding the retained material.
    • Collect the material from the pan at the bottom as well and weigh it. This represents the material that passed the smallest sieve.
    • Repeat these steps for each sieve in the stack and the pan. Ensure you recover as much material as possible from each sieve, using a brush if necessary, without forcing particles through the mesh.
  7. Calculate Percentages:
    • Sum the weights of the material retained on each sieve and in the pan. This sum should be close to the initial total sample weight.
    • Calculate the percentage of material retained on each sieve: (Weight retained on sieve / Total initial sample weight) 100%*.
    • Calculate the cumulative percentage retained: For each sieve, add the percentage retained on that sieve to the cumulative percentage retained on all coarser sieves above it.
    • Calculate the percentage passing each sieve: 100% - Cumulative percentage retained on that sieve. The percentage passing the pan should be 0% (or close to it, allowing for minor losses).

Presenting Results

The results are typically presented in a table showing the sieve size, weight retained, percentage retained, cumulative percentage retained, and percentage passing. A gradation curve is often plotted, showing the sieve size on the x-axis (usually logarithmic scale) and the percentage passing on the y-axis (arithmetic scale).

Example Data Format (Simplified Table):

Sieve Size (e.g., mm or U.S. Sieve No.) Weight Retained (g) Percent Retained (%) Cumulative Percent Retained (%) Percent Passing (%)
Largest Sieve Weight1 Pct1 Pct1 100 - Pct1
Next Sieve Weight2 Pct2 Pct1 + Pct2 100 - (Pct1 + Pct2)
... ... ... ... ...
Smallest Sieve Weightn Pctn Sum Pcts 1 to n 100 - (Sum Pcts 1 to n)
Pan Weightpan Pctpan Total Sum Pcts 0 (ideally)
Total Initial Weight Sum Weights
  • Note: The sum of weights retained plus the pan weight should approximately equal the initial sample weight.

This analysis provides valuable data on the distribution of particle sizes within the sand sample, which is essential for evaluating its suitability for different applications.

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