【国外标准】 Standard Test Method for Shrinkage Factors of Cohesive Soils by the Water Submersion Method

5.1 The shrinkage limit can be used to evaluate the shrinkage potential, crack development potential, and swell potential of earthwork involving cohesive soils.5.2 The shrinkage limit, along with the liquid limit and plastic limit of soil, are often collectively referred to as the Atterberg limits in recognition of their formation by Swedish soil scientist, A. Atterberg. These limits distinguish the boundaries of the several consistency states of cohesive soils.NOTE 1: The quality of the result produced by this standard 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/sampling/inspection/and the like. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.1.1 This test method covers the procedure for determining the shrinkage factors of cohesive soils, using the water submersion technique, whereby the volume of a dried soil pat is determined while suspended in a water bath.1.2 The data obtained following this test method are also used to determine the shrinkage ratio, volumetric shrinkage, and linear shrinkage of the soil.1.3 This test method is applicable only for cohesive soils.1.4 Since this test method is performed only on that portion of a soil which passes the 425-μm (No. 40) sieve, the relative consistency of the tested portion of the soil to the properties of the sample as a whole must be considered when evaluating the entire soil sample.1.5 All recorded and calculated values shall conform to the guide for significant digits and rounding established in Practice D6026.1.5.1 The procedures, used to specify how data are collected/recorded and calculated in this standard, are regarded as the industry standard. In addition, they are representative of the significant digits that should generally be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design.1.6 Units—The values stated in SI units are to be regarded as standard except the sieve designations are shown using the alternative sieve designation in parentheses. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific safety hazards, see Section 8.1.8 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.