Motorized Sand Sieve Shaker for Aggregate Gradation Analysis

Concrete strength, filter design and road bases all depend on one thing: the particle-size distribution of the sand and aggregate going into them. The sieve analysis is the standard way to measure it, and every construction-materials lab teaches it — usually by hand-shaking sieves for ten minutes, which is tiring, inconsistent and hard to standardize across a class. A motorized sieve shaker solves exactly this: it clamps the standard sieve stack and shakes it with a repeatable rotary-tapping motion for a timed run, so results depend on the sample, not on who shook it. This project fabricates such a machine: a motor with an eccentric drive vibrates a spring-suspended platform carrying the sieve nest (4.75 mm down to pan), a timer controls the run, and the student performs the full analysis — weighing, percentage retained, cumulative passing, gradation curve and fineness modulus — from their own machine's output.

1. The sand sample is washed, oven-dried, quartered down to the test quantity and weighed on the balance.
2. The sieve nest is stacked coarsest-on-top down to the pan, the sample is poured onto the top sieve, and the lid and clamp plate are locked.
3. The timer is set (10 minutes per the standard procedure) and the motor is started; the eccentric drives the spring-suspended platform in its shaking motion.
4. At the timer cut-off, the nest is unclamped and each sieve's retained fraction is brushed out and weighed separately.
5. Percentage retained, cumulative percentage retained and percentage passing are computed for each sieve size in the workbook.
6. The gradation curve is plotted on semi-log paper and the fineness modulus is calculated; the sample is classified into its grading zone.
7. The run is repeated on a second sample (e.g. a different sand source) and the two gradation curves are compared in the report.

Tech stack:

• Fabricated MS base cabinet and sieve platform
• Single-phase motor with eccentric drive and link
• Coil spring suspension set
• Brass test sieves: 4.75 mm, 2.36 mm, 1.18 mm, 600 µm, 300 µm + pan and lid
• Adjustable run timer
• Clamp plate with wing-nut fasteners
• Digital weighing balance 0–5 kg (instrument spec)
• Gradation workbook and fabrication drawings

• [Motorized eccentric drive] A single-phase motor with an eccentric and connecting link gives the platform a repeatable rotary-tapping motion — the standard shaker action, without hand fatigue.
• [Standard sieve nest] Brass test sieves (4.75 mm, 2.36 mm, 1.18 mm, 600 µm, 300 µm) plus lid and receiving pan clamp as a nest, matching the sizes used in the syllabus test.
• [Spring-suspended platform] The sieve platform rides on coil springs, isolating vibration from the base and giving the free, consistent motion the analysis assumes.
• [Timer-controlled runs] An adjustable timer ends each run at the set duration, so every test in the report uses the same shaking time.
• [Quick sieve clamping] A top clamp plate with wing nuts locks the nest in seconds and releases it for weighing between runs.
• [Gradation workbook] Weighing tables, percentage-retained and cumulative-passing calculations, semi-log gradation plotting sheets and a fineness-modulus worked example.
• [Sample preparation guide] Washing, oven-drying and quartering procedure so the tested sample is representative — the step most student reports skip.

• Complete motorized sieve shaker (assembled and tested)
• Standard brass sieve nest with pan and lid
• Digital weighing balance
• Sample preparation and test procedure manual
• Gradation calculation workbook with plotting sheets
• Fabrication drawings of the shaker
• Project report PDF (theory, procedure, readings, analysis)
• PPT presentation for final review
• Viva Q&A preparation document (gradation, fineness modulus, grading zones)

• The machine performs the standard sieve analysis; it does not measure particle shape (flakiness/elongation need separate gauges) or fines below 75 µm (needs wet sieving).
• Results depend on proper sample preparation — an unwashed or damp sample biases the fines fraction, which the manual addresses explicitly.
• The eccentric gives a fixed shaking amplitude; it cannot reproduce every commercial shaker's motion profile, so cross-lab comparison needs the same procedure.
• Sieve meshes wear with abrasive aggregates; the manual covers mesh inspection and the wear limit.
• The balance and oven-drying step assume access to a basic lab oven or a documented sun-drying alternative.