Laserfiche WebLink
STS Soil Classification System <br /> <br /> UNIFIED SOIL CLASSIFICATION SYSTEM <br /> Major Divisions Group <br /> Symbols Typical Names Laboratory Classification Criteria <br /> ~ ~ ~' Well graded gravels, gravel- <br /> <br /> -~ ~ ce GW : C, ¥,~r~4;Cc=~bet~e~la~3 <br /> ~= sand mi~ures, little or no fines ~ = <br /> . · Poorly graded gravels, gravel- E E <br /> ~ ~ ~ GP m ~ Not meeting all gradation requirements for G~ <br /> - ~ sand mixtures, little or no fines <br /> ~ ~ ~ Atterberg limits below <br /> · O~ ~ Silty gravels, gravel-sand-clay <br /> ~ ~ ~ GM N '5 "A" line or P.I. less than Above "A" line with <br /> ~ ~ ~ ~ & mixtures <br />  · E 4 P.I. baleen 4 and 7 <br /> ~ ~ ~ are borderline cases <br /> z ~ ~ ~ ~ GC Clayey gravels, gravel-sand-~ ~ ~ ~ Atte~erg limits above requiring use of dual <br /> ~ ~ ~ ~ · "A" line wi~ P.I. symbols <br /> ~ O ~ clay mixtures ~ ~ greater than 7 <br /> ~ ~ Well graded sands, gravelly <br /> e.~' '~ ~ ~ sands, little or no fines <br /> ~ <br /> ~ '-~ ~ ~ Poorly graded sands, gravelly ~ ~ ~: ~ ~ i <br /> -- ~ ~ ~ SP ~ ~ ~ ~ ~ : Not meeting all gradation requirements for SW <br /> ~ ~ '~ ~ sands, traces or no fines <br /> <br /> ~ ~ = ~ - ~ Atterberg limits below Limits plotting in <br /> ~ d ~ Silty sands, sand and silt <br /> ~ ~o~ z ~ ~ SM 8 ~ [~ "A" line or P.I. less that hatched zone with <br /> ~ ~ E mixtures <br /> ~ ~ ~ 8 [ ~ ~ ~m ~ 4 P.I. between4and7 <br /> ~ ~~ [ ~ ~ ~ ~ ~ are borderline cases <br /> c ~ .D ~ ~ ~ ~ o c w requiring use of dual <br /> - - '~ ' ~ Atte~erg limits above <br /> e ~ ~ SC Clayey sands, sand and clay '~ ~ ~ ~ ~ symbols <br /> ~ o o "A" line with P.I. <br /> ~ o ~ ~ mixtures <br /> ~ ~ ~ ~ E greater than 7 <br /> Inorganic silts, rock flour, silty or Liquid Limit Plastici~ Cha~ <br /> ML clayey fine sands or clayey silts 60 <br /> with slight plasticity <br /> / <br /> '~ ~ Inorganic clays of Iow to mediu~ 50 -- <br />~ ~ ~ CL plasticity, gravelly clays, sandy <br />~ ~ ~ days, ~ilty dayg, lean ~la~ <br /> ~ ~ Or~ani~ silt~ and or~ani~ silty <br /> 'g OL <br />~ ~ days o~ ~ pla~tidty <br />~ ~H diatoma~ou~ ~ne gilty goilg, - <br />.-'- <br />~ ~ Inor~ani8 ola~g o~ffi~ff pla~tidt~, 4 I OL-~L <br />~ ~ ~ ~, 0 ~ 20 30 40 ~0 ~0 ~0 80 ~0 ~00 <br />~ : '~ Or~anio ola~g, gilt~ or ~ilt and <br />~ ~ .~ OH <br />~ ~ day mixtum~ ~[ medium to ~i~ff For dagsi~oation o[ fin~-~rained goil~ and ~ne fraction o[ ~oar~e- <br />~ plastidt~ ~rained soilg. <br /> ~ ~ '~ Pt Peat an~ otffer ffi~ffly or~ani~ A~rber~ Limitg plottin~ in ffatoffe~ area are ~orderline <br /> ~ ~ goils ~la~gi~oation~ requidn~ uge of dual gym~olg. <br /> <br /> ,/ <br />.' / OH orUH <br /> CL _ <br /> CL-ML <br /> <br /> <br />