Agenda - Public Works Committee - 02/21/2023

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UNIFIED SOIL CLASSIFICATION SYSTEM ASTM Designations: D 2487, D2488 Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Coarse -Grained Soils More than 50°0 retained on No. 200 sieve Fine -Grained Soils 50°oor more passes the No. 200 sieve (see Plasticity Chart below) Highly organic soil ( a U 50 40 20 Gravels More than 50° o coarse fraction retained on No. 4 sieve Sands 50°oor more of coarse fraction passes No. 4 sieve Silts and Clays Liquid limit less than 50 Silts and Clays Liquid limit 50 or more SIEVE ANALYSIS 1-s°' I'Pemng un o- =15n,n 1 =25nn Sev, rmneer 0 'J 40 n) 140 20) ) 20 0 E DIi= 0075n, Clean Gravels Less than 5°0 finesc Gravels with Fines more than 12° o fines c Clean Sands Less than 5°0 finesD Sands with Fines more than 12° o fines D inorganic organic inorganic organic PARTICLE SIZE IN MILLIMETERS _ r>y! 15 _ z2) a one Term Boulders Cobbles Gravel Sand Fines (silt R clay) -L'r - 25: _5 EN.. Dye1175. 15 'b ADDITIONAL TERN Grain Size Particle Size Over 12" 3" 12" #4 sieve to #200 to #4 sieve Pass #200 sieve Moisture/Frost Condition (MC Column) D (Dry): Absence of moisture, dusty. dry to touch. M (Moist): Damp. although free water not visible. Soil may still have a high water content (over "optimum"). W (Wet' Free water visible. intended to Waterbearing): describe non -plastic soils. Waterbearing usually relates to sands and sand with silt. F (Frozen): Soil frozen PLASTICITY INDEX (PI) Cu_4 and 1_Cc_3E Cu=4 and/or 1-- Cc: 3E Fines classify as ML or MH Fines classify as CL or CH Cu_6 and 1_Cc_3E Cu=6 and/or 1-- Cc=3E Fines classify as ML or MH Fines classify as CL or CH PF 7 and plots on or above "A" line' P114 or plots below "A" line' Liquid limit —oven dried -n 75 Liquid limit — not dried PI plots on or above "A" line PI plots below "A" line Liquid limit —oven dried -n 75 Liquid limit — not dried Primarily organic matter, dark in color. and organic in odor E„ 50 - 40 - 30 - 20 - 10- For classification of finearained soils and finearained fracton of coarse-crained mils Equation of "A" -line Horizontal at PI = 4 to LL = 25 5 then PI = 0 73 (L1-20) Equation of "U"-line Vercal at LL= 16 to PI=7 then PI = 0 9 (LL-8) 40 / , CL-ML • 0 10 16 20 ML OL Soil Classification Group Group NameB Symbol GW Well graded gravelF GP Poorly graded gravelF GM Silty gravelF G H GC Clayey gravelF G H SW Well -graded sand' SP Poorly -graded sand' SM Silty sandGT SC Clayey sandGH1 CL Lean clay'`', M NIL Silt"-' "1 OL Organic clay''LMN Organic silt'. L M 0 CH Fat clay''LM MH Elastic silt'' M OH Organic clay'' L M P Organic silt'. L M Q PT Peat' MH„,OH 30 40 50 PJ LIQUID LIMIT (LL) Plasticity Chart 70 8 ) 160 110 AMERICAN ENGINEERING TESTING, INC. AMERICAN Notes ABased on the material passing the 3-in (75-mm) sieve. BIf field sample contained cobbles or boulders. or both. add' with cobbles or boulders. or both" to group name. cGravels with 5 to 12° o fines require dual symbols: GW-GM well -graded gravel with silt GW-GC well -graded gravel with clay GP -GM poorly graded gravel with silt GP -GC poorly graded gravel with clay DSands with 5 to 12° o fines require dual symbols: SW-SM well -graded sand with silt SW -SC well -graded sand with clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay ECU — D60 iD10. CC — (D3o)2 Dlos D60 FIf soil contains L15° o sand. add' with sand" to group name. GIf fines classify as CL-ML. use dual symbol GC -GM, or SC-SM. HIf fines are organic, add "with organic fines" to group name. 'If soil contains _15° o gravel. add "with gravel" to group name. If Atterberg limits plot is hatched area. soil is a CL-ML silty clay. ''If soil contains 15 to 29° o plus No. 200 add "with sand" or "with gravel". whichever is predominant. LIf soil contains `30° o plus No. 200, predominantly sand. add "sandy" to group name. MIf soil contains - 30° o plus No. 200, predominantly gravel. add "gravelly" to group name. NP1-4 and plots on or above "A" line. °Pl -4 or plots below "A" line. PPl plots on or above "A" line. VI plots below "A" line. 'Fiber Content description shown below. NOLOGY NOTES USED BY AET FOR SOIL IDENTIFICATION AND DESCRIPTION Gravel Percentages Term Percent A Little Gravel With Gravel Gravelly 3°4, 15°0 - 29°0 ?0°°-50°0 Layering Notes Laminations: Layers less than thick of differing material or color. Lenses: Pockets or layers greater than '2" thick of differing material or color. Consistencv of Plastic Soils Term N-Value. BPF Very Soft Soft Firm Stiff Very Stiff Hard Relative Density of Non -Plastic Soils Term N-Value. BPF less than 2 Very Loose 2 - 4 Loose 5 - 8 Medium Dense 9 - 15 Dense 16 - 30 Very Dense Greater than 30 Peat Description Fiber Content Term (Visual Estimate) Fibric Peat: Greater than 67° 0 Hemic Peat: 33 — 67° 0 Sapric Peat: Less than 3 3° o 0-4 5-10 11-30 31-50 Greater than 50 Organic Description (if no lab tests) Soils are described as organic, if soil is not peat and is judged to have sufficient organic fines content to influence the Liquid Limit properties. Sliehth oceanic used for borderline cases. Root Inclusions With roots: Judged to have sufficient quantity of roots to influence the soil properties. Trace roots: Small roots present. but not judged to be in sufficient quantity to significantly affect soil properties. 01CLS021 (01/2022) AMERICAN ENGINEERING TESTING, INC.