This practice describes a system for classifying mineral and organo-mineral soils for engineering purposes based on laboratory determination of particle-size characteristics, liquid limit, and plasticity index and shall be used when precise classification is required. This classification system identifies three major soil divisions, which are further subdivided into a total of 15 basic soil groups. Based on the results of visual observations and prescribed laboratory tests, a soil is catalogued according to the basic soil groups, assigned a group symbol(s) and name, and thereby classified.
Material passing #10 sieve of 115 grams for sandy soil and 65 grams for silt and clay soil
Atterberg limits, classification, clay, gradation, gravel, laboratory classification, organic soils, sand, silt, soil classification, soil tests, USCS