Poorly Graded

Poorly Graded Soil

Poorly Graded: In the soil classification process of geology, poorly graded soil represents a sedimentary soil sample that only displays one or a few of the numerous other possible grain sizes for that soil classification, in accordance with the Unified Soil Classification System (USCS). For example, a poorly graded sand (SP) may only comprise fine and medium grains of sands, but not coarse grains. Whereas a well graded sand (SW) comprises fine, medium and coarse grains of sand. Similarly, in the geotechnical and engineering geology branches of geology, the term poorly graded is also synonymous with the term “well sorted.”

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