Silt Material passing a mm (No. 200) that is and has little strength when dry (PI < 4). Peat Soil of vegetable matter. Note that these definitions are Unified Soil Classification system definitions and are slightly different than . The table below shows the Unified Soil Classification system (ASTM). Unified Soil Classification (USC) System (from ASTM D 2487) Group Major Divisions Typical Names Symbol Well-graded gravels and GW Gravels gravel-sand mixtures, 50% or little or no fines Clean more of Gravels Poorly graded gravels course and gravel-sand fraction GP mixtures, little or no retained fines on the 4.75 Silty gravels, GM Gravels sand-silt mixtures (No. 4) with Course-Grained Soils sieve Fines Clayey gravels, GC More than 50% retained sand-clay mixtures on the 0.075 (No. 200) sieve Well-graded sands and SW gravelly sands, little or Sands no fines 50% or Sands more of Poorly graded sands and course SP gravelly sands, little or fraction no fines passes the 4.75 Silty sands, SM Sands (No. 4) mixtures with sieve Fines Clayey sands, SC mixtures Inorganic very fine ML sands, rock four, silty or Fine-Grained Soils clayey fine sands Silts and Clays More than 50% passes Liquid Limit the 0.075 mm Inorganic clays of low 50% or less (No. 200) sieve to medium plasticity, CL gravelly/sandy/silty/lean clays
Silt Material passing a (No. 200) that is and has little strength when dry (PI < 4). Peat Soil of vegetable matter. Note that these definitions are Unified Soil Classification system definitions and are slightly different than . The table below shows the Unified Soil Classification system (ASTM). Unified Soil Classification (USC) System (from ASTM D 2487) Major Divisions Group Symbol Typical Names Course-Grained Soils More than 50% retained on the 0.075 (No. 200) sieve Gravels 50% or more of course fraction retained on the 4.75 mm (No. 4) sieve Clean Gravels GW Well-graded gravels and gravel-sand mixtures, little or no fines GP Poorly graded gravels and gravel-sand mixtures, little or no fines Gravels with Fines GM Silty gravels, mixtures GC Clayey gravels, mixtures Sands 50% or more of course fraction passes the 4.75 (No. 4) sieve Sands SW Well-graded sands and gravelly sands, little or no fines SP Poorly graded sands and gravelly sands, little or no fines Sands with Fines SM Silty sands, sand-silt mixtures SC Clayey sands, sand-clay mixtures Fine-Grained Soils More than 50% passes the 0.075 mm (No. 200) sieve Silts and Clays Liquid Limit 50% or less ML Inorganic very fine sands, rock four, silty or clayey fine sands CL Inorganic clays of low to medium plasticity, gravelly/sandy/silty/lean clays
ASTM%20Terminology.docx