6.6. SR 08-19-2002 - Laserfiche WebLink

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CLASSIFICATION OF SOILS FOR ENGINEERING PURPOSES ASTM Designation: D 2487 (Based on Unified Soil Classification System) AMERICAN ENGINEERING TESTING, INC. Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Soil Classification Group Group Namee Symbol Coarse-Grained Soils Gravels Clean Gravels More than 50% retained on More than 50% coarse Less than 5% finesc No. 200 sieve fraction retained on No. 4 sieve Cu_>4 and 1_,5Cc~3~= GW Well graded gravel~ Cu~4 and/or 1~'Cc=,3E GP Poorly graded gravel~ Gravels with Fines More than 12% finesc Fines classify as ML or MH GM Silty gravel~'G'~/ Fines classify as CL or CH GC Clayey gravelF's'~ Sands Clean Sands .50% or more al' coarse Less than 5% fines° fraction passes No. 4 sieve Cu~6 and t_~ Cc~3~ SW Well-graded sand; Cu<6 and/or 1>Cc>3E SP Poorly graded sand/ Sands with Fines More than 12% tines° Fines classify as ML or MH SM Silty sandG.'~,/ Fines classify as CL or CH SC Clayey sands'H'; Fine-Grained Soils Silts and Clays inorganic PI~,7 and plots on or above CL Lean clay~('L''~ 50% or more passes the Liquid limit less than 50 "A" lineJ No. 200 sieve PI c4 or plots below "A" ML SiltK'cM lineJ organic Liduid limit - oven dried aL Organic cJ~.yK'L'M'N <0.75 · Liquid limit - not dried Organic siltK'/-'M'° Silts and Clays inorganic Liquid limit 50 or more PI plots on or above "A" line CH Fat ~'layK'cM PI plots below "A" line MH Elastic siltK'L'M organic Liquid limit - oven dried OH Organic clayK'L'M'~' <0.75 Liquid limit - not dried Organic siltK'L'M'° Highly organic soils Primarily organic matter, dark in color, and organic odor PT Peat ABased on the material passing the 3-in. (75-mm) sieve, Bit field sample contained cobbles or boulders, or both, add "with cobbies or boulciers, or both" to group name, CGravels with S to 12% fines reciuire dual symbols: OW-GM well-graded gravel with silt GW-GC welPgraded gravel with clay GP-GM poorly graded gravel with silt GP-GC poorly graded gravel with clay ~Sands with 5 lo 12% fines reciuire dual symbols: SW-SM well-graded sand with silt SW-SC well~gracied sand with clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay '~F~~~-° PARTICLE SIZE IN MILLIMETERS C o]cLs°2 (5/oo) ECu - DSO /D10 Cc ~ {D30)2 D10 x 050 Fit soil contains:~-15% senti, acid "with sand" to group Git fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. Hit fines are organic, add "with organic lines" to group Ill so. ii contains_15% gravel add "with gravel" to group Jif Atterberg limits plot in belched area, soll is a CL~ML. silty clay. Kit soil contains 15 to 29% plus No. 200, acid "with sand" or "with gravel." whichever is preciominanL Lit soil contains_30% plus no. 200, predominantly sand, add "sandy" to to group name. Mit soil contains-~30% plus No. 200, predominantly gravel, add "gravelly" to group name. NpI_~4 and plols on or above "A" line. °PI.,~4 or plots below "A' line. PPI plots on or above "A" line. OPI plots below "A" line. x I-- I-. 1.1 6O For classi'ficotion of fJne-~r~ined soils '/ and fine-~roined fraction aY coarse-stained/ _ soils. Horizontal at PI-4 to LL-25.5,~ then PI-0.7, (LC-Z0) / , O~ ..~ Vertical at LL=I6 t0 P // then Pi = 0.9 (LL-8} / /// ' 50 I0 Ia IS Z0 ~0 40 50 60 ?0 BO SO IIX) Il0 LIQUID LIMIT (LL}