【国外标准】 Standard Test Method for Effect of Organic Impurities in Fine Aggregate on Strength of Mortar

5.1 This test method is of significance in making a final determination of the acceptability of fine aggregates with respect to the requirements of Specification C33/C33M concerning organic impurities.5.2 This test method is applicable to those samples which, when tested in accordance with Test MethodC40/C40M, have produced a supernatant liquid with a color darker than the standard listed in Table 1 of C40/C40M (Organic plate No. 3, Gardner Color Standard No. 14, Circular Disk No. 14 or prepared color solution).5.3 Many specifications provide for the acceptance of fine aggregate producing a darker color in the Test Method C40/C40M test, if testing by this test method indicates the strength of the mortar cubes prepared with the unwashed fine aggregate is comparable to the strength of mortar cubes made with the washed fine aggregate.1.1 This test method covers the determination of the effect on mortar strength of the organic impurities in fine aggregate, whose presence is indicated using Test Method C40/C40M. Comparison is made between compressive strengths of mortar made with washed and unwashed fine aggregate.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. Some values have only SI units because the inch-pound equivalents are not used in the practice.NOTE 1: Sieve size is identified by its standard designation in Specification E11. The alternative designation given in parentheses is for information only and does not represent a different standard sieve size1.3 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.(Warning—Fresh hydraulic cementitous mixtures are caustic and may cause chemical burns to exposed skin and tissue upon prolonged exposure.)21.4 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.