AASHTO T21-2005(2009) 国外国际标准.pdf

Standard Method of Test for Organic Impurities in Fine Aggregates for Concrete AASHTO Designation: T 21-05 (2009)1 ASTM Designation: C 40-04 1. SCOPE 1.1. This test method covers two procedures for an approximate determination of the presence of injurious organic compounds in fine aggregates that are to be used in hydraulic cement mortar or concrete. One procedure uses a standard color solution and the other uses a glass color standard. 1.2. This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards : M 6, Fine Aggregate for Hydraulic Cement Concrete R 16, Regulatory Information for Chemicals Used in AASHTO Tests T 2, Sampling of Aggregates T 71, Effect of Organic Impurities in Fine Aggregate on Strength of Mortar T 248, Reducing Samples of Aggregate to Testing Size 2.2. ASTM Standard : D 1544, Standard Test Method for Color of Transparent Liquids (Gardner Color Scale) 3. SIGNIFICANCE AND USE 3.1. This test method is of significance in making a preliminary determination of the acceptability of fine aggregates with respect to the requirements of M 6. 3.2. The principal value of this test method is to furnish a warning that organic impurities may be present. When a sample subjected to this test produces a color darker than