Laserfiche WebLink
UNIFIED SOIL CLASSIFICATION SYSTEM <br /> Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests' Soil Classification <br /> Group <br /> Symbol Group Name° <br /> Coarse Grained Soils Gravels Clean Gravels Cu=4 and 1=Cc s'3E GIN Well-graded grave{ <br /> More than 50%retained More than 50%of coarse Less than 5%fin ,` Cu<4 d'or 1 Cc 3' GP <br /> fra0on retained on a .> > PODS graded ' <br /> on No.200 sieve No.4 sieve Gravels with Fines More Fries dame/as ML or MH GM Silty graver" <br /> than 12%fines, Fines classify as CL or CH GC Clayey gravel.°" <br /> Sands Clean Sands Cu=6 and 1 Cc=3K SW Well-graded sand <br /> 50%or more of coarse Less than 5%fines° <br /> traction passes Cu<6andfor 1>Cc>3E SP Poorly graded sand <br /> No.4 sieve Sands with Fines Fines classify as ML or MH SM Silty sanctwo <br /> More than 12%fines' Fines Classify as CL or CH SC Clayey sand"' <br /> Fine-Grained Soils Ms and Clays inorganic PI>7 and plots on or above"A"Um' CL Lean day" <br /> 50%or more passes the timid Emit less than 5€I <br /> No.200 sieve PI<4 or plats "'-"below"A'line' ML Silt <br /> organic Liquid limit-oven dried Organic dayY"" <br /> 0.75 OL <br /> Liquid limit-not dried Organic siltKI," <br /> Silts and Clays inorganic PI plots on or above"A"line CH Fat day" <br /> Liquid emit 50 or more PI plots below'A"line MH Elastic Silf`" <br /> organic Liquid limit-oven dried 0.75 OH Organic day'"`Mr <br /> Liquid limit-not dried Organic silt'`" <br /> Highly organic sots Primarily organic reader,dark in color,and organic odor PT Peat <br /> "Based on the material passing the 3-in.(75-man)sieve if fry are organic,add'with organic fines'to group mane. <br /> a If field sample contained cobbles or boulders,or both,add"with cobbles 'If soil contains>_15%gravel,add'with gravel"to group name. <br /> or boulders,or both"to group name. ]If Atterberg limits plot in shaded area,sod is a CL-ML,silty day. <br /> °Gravels with 5 to 12%fines require dual symbols: GW-GM well-graded K If soil contains 15 to 29%plus No.200,add with sand'or"with <br /> gravel with silt;GW-GC well-graded gravel with clay,GP-GM poorly gravel,"whichever is predominant <br /> graded gravel with silt,GP GC poorly graded gravel with clay. `If soil contains'30%plus No.200 predominantly sand,add <br /> °Sands with 5 to 12%fines require dual symbols: SW-SM well-graded "sandy'to group name. <br /> sand with silt.SW-SC well-graded sand with day,SP-SM poorly graded e <br /> sand with silt,SP-SC poorly graded sand with clay If soil contains L 30%plus No.200,predominantly gravel,add <br /> "gravelly to group name. <br /> ECu=D)1Dto Cc= tD-) "PI>_4 and plots on or above`A"fine_ <br /> De x De °PI c 4 or plots below"A"line. <br /> r If soil contains L 15%sand,add"with sand"to group name. °PI plots on or above"A"line_ <br /> cif fines classify as CL-ML,use dual symbol GC-GM,or SC-SM. °PI plots below'A'line. <br /> 60 f ' ' <br /> I For classification of fine-grained <br /> soils and fine-grained fraction <br /> 50 _of coarse-grained sot p a <br /> Equation Of`A"-Meo'5 1' •P <br /> 9 1 Horizontal at PI.4 to LL=-25.5. f <br /> x 40 1— then PI=0.73(LL-20) `� �� _.-...i _ <br /> 3 Equation of`U"-lire (A <br /> Z l vertical at LL=1s to PI=7; ir Ci <br /> - 30 ` then Pk0.9(LL-8) <br /> , <br /> U i & <br /> a MH or OH : 1 <br /> toi- <br /> 7 <br /> 4, MLarOL <br /> 0 10 16 20 30 40 50 60 30 60 90 100 110 <br /> LIQUID LIMIT(LL) <br /> lierracon - <br /> 81135080 <br />