SME
Soil Mechanics · Problem type
USCS major divisions
Use this for “Is a clayey sand coarse grained or fine grained in the Unified Soil Classification System?”
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Which major division of the USCS is each soil in?
Tap a card, then tap its group.
Weigh what the No. 200 sieve holds back: more than half retained is coarse grained, otherwise fine grained, unless the soil is mostly plant matter.
Assumptions
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USCS (Unified Soil Classification System, ASTM D2487) groups soils by grain size first.
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Coarse grained: more than half the soil stays on the No. 200 sieve (0.075 mm).
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Group symbols: first letter G gravel, S sand, M silt, C clay; second W, P, L or H.
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