08-08-2016 Council Packet - Laserfiche WebLink

Home Browse Search

A-7 A-7-5 A-7-6 Sieve Analysis, Percent passing: No. 10 (2.00 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 max. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 40 (0.425 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30 max. 50 max. 51 min. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . No. 200 (0.075 mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 max. 25 max. 10 max. 35 max. 35 max. 35 max. 35 max. 36 min. 36 min. 36 min. 36 min. Characteristics of Fraction Passing No. 40 (0.425 mm) Liquid limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 max. 41 min. 40 max. 41 min. 40 max. 41 min. 40 max. 41 min. Plasticity index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N.P. 10 max. 10 max. 11 min. 11 min. 10 max. 10 max. 11 min. 11 min. General Ratings as Subgrade . . . . . . . . . . . . . . . . . . . . . . . Definitions of Gravel, Sand and Silt-Clay 01CLS022 (07/11)AMERICAN ENGINEERING TESTING, INC. A-2-5 Stone Fragments, Gravel and Sand Fair to Poor A-6 The placing of A-3 before A-2 is necessary in the "left to right elimination process" and does not indicate superiority of A-3 over A-2. Usual Types of Significant Constituent Materials A-1-a A-1-b Group Classification The terms "gravel", "coarse sand", "fine sand" and "silt-clay", as determinable from the minimum test data required in this classification arrangement and as used in subsequent word descriptions are defined as follows: Granular Materials Silt-Clay Materials A-1 A-2 A-2-6 A-2-7 . . . . 6 max. Fine Sand Silty or Clayey Gravel and Sand Silty Soils Clayey Soils Plasticity index of A-7-5 subgroup is equal to or less than LL minus 30. Plasticity index of A-7-6 subgroup is greater than LL minus 30. A-3 A-2-4 The term "silty" is applied to fine material having plasticity index of 10 or less and the term "clayey" is applied to fine material having plasticity index of 11 or greater. AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS AASHTO SOIL CLASSIFICATION SYSTEM Classification of Soils and Soil-Aggregate Mixtures GRAVEL - Material passing sieve with 3-in. square openings and retained on the No. 10 sieve. COARSE SAND - Material passing the No. 10 sieve and retained on the No. 40 sieve. FINE SAND - Material passing the No. 40 sieve and retained on the No. 200 sieve. COMBINED SILT AND CLAY - Material passing the No. 200 sieve Excellent to Good Group A-8 soils are organic clays or peat with organic content >5%. BOULDERS (retained on 3-in. sieve) should be excluded from the portion of the sample to which the classificaiton is applied, but the percentage of such material, if any, in the sample should be recorded. (35% or less passing No. 200 sieve) (More than 35% passing No. 200 sieve) General Classification A-4 A-5 -10 0 10 20 30 40 50 100 90 80 70 60 50 40 30 20 15 35 0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 3 0 4 0 5 0 6 0 7 0 8 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 1 0 0 1 4 0 1 8 0 L I Q U I D L I M I TPLASTICITY I N D E X P E R C E N T P A S S I N G N O . 2 0 0 S I E V E P A R T I A L G R O U P I N D E X GROUP INDEX CHART Group Index (GI) = (F-35) [0.2+0.005 (LL-40) ] + 0.01 (F-15) (PI-10) where F = % Passing No. 200 sieve, LL = Liquid Limit, and PI = Plasticity Index. When working with A-2-6 and A-2-7 subgroups the Partial Group Index (PGI) is determined from the PI only. When the combined Partial Group Indices are negative, the Group Index should be reported as zero. A- 2 - 6 a n d A - 2 - 7 82% Passing No. 200 sieve LL = 38 PI = 21 PGI = 8.9 for LL PGI = 7.4 for PI GI = 16 Then:Example: 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 Sub-GroupA-7-5 S u b - G r o u p A - 7 - 6A-7A-5 A-4 A-6 PI = LL - 30 PLASTICITY INDEX (PI) Liquid Limit and Plasticity Index Ranges for the A-4, A-5, A-6 and A-7 Subgroups Li q u i d L i m i t