Which combination of sieve sizes are used in the nested stack for washing?

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Multiple Choice

Which combination of sieve sizes are used in the nested stack for washing?

Sieve nesting in washing is used to separate material into three size ranges so you can manage product quality and remove unwanted fines. The top opening is 2.36 mm, so anything larger stays on the top sieve while smaller particles pass through. The next sieve has a 1.18 mm opening, catching the next size range and allowing only smaller material to pass further. The bottom sieve, at 75 µm, collects the finest material—the sands and the fines you want to segregate from the coarser fractions. This combination—2.36 mm, 1.18 mm, and 75 µm—gives you a practical three-tier split: a coarse fraction, a sand-like middle fraction, and the fines. It matches the typical washing practice in which you recover or discard fines separately, while keeping the larger aggregates clean for asphalt mix quality. Other options don’t align with this three-product separation: their sizes would either lump too much material into the coarse or fine fraction or fail to create a distinct sand-like middle fraction, reducing the effectiveness of the wash and the usefulness of the separated products.

Sieve nesting in washing is used to separate material into three size ranges so you can manage product quality and remove unwanted fines. The top opening is 2.36 mm, so anything larger stays on the top sieve while smaller particles pass through. The next sieve has a 1.18 mm opening, catching the next size range and allowing only smaller material to pass further. The bottom sieve, at 75 µm, collects the finest material—the sands and the fines you want to segregate from the coarser fractions.

This combination—2.36 mm, 1.18 mm, and 75 µm—gives you a practical three-tier split: a coarse fraction, a sand-like middle fraction, and the fines. It matches the typical washing practice in which you recover or discard fines separately, while keeping the larger aggregates clean for asphalt mix quality.

Other options don’t align with this three-product separation: their sizes would either lump too much material into the coarse or fine fraction or fail to create a distinct sand-like middle fraction, reducing the effectiveness of the wash and the usefulness of the separated products.

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