Note 5: Notwithstanding the statements on precision and bias contained in this standard: The precision of this test method is dependent on the competence of the personnel performing it and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing. Users of this test method are cautioned that compliance with Practice D3740 does not in itself assure reliable testing.
Reliable testing depends on several factors; Practice D3740 provides a means for evaluating some of those factors. Note 1: Use of this standard will result in a single classification group symbol and group name except when a soil contains 5 to 12% fines or when the plot of the liquid limit and plasticity index values falls into the crosshatched area of the plasticity chart. In these two cases, a dual symbol is used, for example, GP-GM, CL-ML.
![Aashto Material Classification Aashto Material Classification](/uploads/1/2/5/4/125405587/306199274.jpg)
When the laboratory test results indicate that the soil is close to another soil classification group, the borderline condition can be indicated with two symbols separated by a slash. The first symbol should be the one based on this standard, for example, CL/CH, GM/SM, SC/CL. Borderline symbols are particularly useful when the liquid limit value of clayey soils is close to 50.
Comparison: AASHTO & Unifical Soil Classification System Soil Engineering As given in Table 4.2, the soils are broadly classified into two categories: (1) Coarse-Grained Soils: The gravel and sand are further divided into subgroups as: F = Coarse material containing fines not.
These soils can have expansive characteristics and the use of a borderline symbol (CL/CH, CH/CL) will alert the user of the assigned classifications of expansive potential. 1.7 This practice offers a set of instructions for performing one or more specific operations.
This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects.
The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. 1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents (purchase separately)ASTM StandardsTest Method for Materials Finer than 75-m (No. 200) Sieve in Mineral Aggregates by WashingTest Method for Sieve Analysis of Fine and Coarse AggregatesPractice for Reducing Samples of Aggregate to Testing SizeTerminology Relating to Soil, Rock, and Contained FluidsTest Methods for Determining the Amount of Material Finer than 75-m (No.
The AASHTO Soil Classification System was developed by the, and is used as a guide for the and soil-aggregate mixtures for purposes. The classification system was first developed by Hogentogler and in 1929, but has been revised several times since.AASHTO Soil Classification System (from AASHTO M 145 or ASTM D3282)General ClassificationGranular Materials (35% or less passing the 0.075 mm sieve)- Materials (35% passing the 0.075 mm sieve)Group ClassificationA-1A-3A-2A-4A-5A-6A-7A-1-aA-1-bA-2-4A-2-5A-2-6A-2-7A-7-5 A-7-6,% passing2.00 mm (No. 10)50 max0.425 (No. 40)30 max50 max51 min0.075 (No. 200)15 max25 max10 max35 max35 max35 max35 max36 min36 min36 min36 minCharacteristics of fraction passing 0.425 mm (No. 40)40 max41 min40 max41 min40 max41 min40 max41 min6 maxN.P.10 max10 max11 min11 min10 max10 max11 min11 minUsual types of significant constituent materialsstone fragments, gravel and sandfine sandsilty or clayey gravel and sandsilty soilsclayey soilsGeneral rating as a subgradeexcellent to goodfair to poorPlasticity index of A-7-5 subgroup is equal to or less than the LL - 30.
Plasticity index of A-7-6 subgroup is greater than LL - 30References.