AASHTO M 143-2014 Standard Specification for Sodium Chloride.pdf

1、Standard Specification for Sodium Chloride AASHTO Designation: M 143-14 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4c M 143-1 AASHTO Standard Specification for Sodium Chloride AASHTO Designation: M 143-14 1. S

2、COPE 1.1. This specification covers sodium chloride used for pre-treatment of and deicing road surfaces and for road construction and maintenance applications. Other uses may also be appropriate. 1.2. This specification is applicable for orders in either SI units or inch-pound units. SI and inch-pou

3、nd units are not necessarily equivalent. Inch-pound units are shown in brackets in the text for clarity, but they are applicable values when the material is ordered. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: T 27, Sieve Analysis of Fine and Coarse Aggregates 2.2. ASTM Standards: D1429, Standard

4、Test Methods for Specific Gravity of Water and Brine E534, Standard Test Methods for Chemical Analysis of Sodium Chloride 3. CLASSIFICATION 3.1. This specification covers sodium chloride mined from natural deposits, commonly known as rock salt, as well as evaporated from naturally occurring or hydra

5、ulically produced brine. The following two types and grades are commonly recognized: 3.1.1. Type IUsed for deicing pavement surfaces or in aggregate stabilization: 3.1.1.1. Grade 1Standard grading for general use as described in Section 6.1. 3.1.1.2. Grade 2Special grading as described in Section 6.

6、1. 3.1.2. Type IIUsed in aggregate stabilization and applications other than deicing pavements. 3.2. This specification also covers sodium chloride used in the form of brine defined as a liquid saturated with chloride. 4. ORDERING INFORMATION 4.1. Orders for sodium chloride under this specification

7、shall include the following information as necessary to adequately describe the desired product: 4.1.1. AASHTO designation and year of issue; 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 143-2

8、 AASHTO 4.1.2. Type and grade (if appropriate) of product required; 4.1.3. Quantity required; 4.1.4. Delivery location; 4.1.5. Special requirements (including special grading requirements, packaging size, marking requirements, and special shipping instructions), if required; and 4.1.6. Testing, lot

9、size, and certification, if required. 5. CHEMICAL REQUIREMENTS 5.1. The chemical composition for the sodium chloride ordered shall conform to a minimum of 95 percent sodium chloride (NaCl). 5.2. Brine shall be at a solution concentration of 23.3 percent NaCl by weight. Note 1Agencies may allow a var

10、iation of the required concentration when considering expected minimum roadway temperatures and performance needs based on the phase diagram shown in Figure X1.1. 6. PHYSICAL REQUIREMENTS 6.1. Grading: 6.1.1. Type IThe grading of Type I sodium chloride, when sampled at the point of delivery and test

11、ed in accordance with T 27, shall conform to the requirements of Table 1. Table 1Grading Requirements Sieve Size % Passing Grade 1 Grade 2 19.0 mm 3/4in. 100 12.5 mm 1/2in. 100 9.5 mm 3/8in. 95 to 100 4.75 mm No. 4 20 to 95 20 to 100 2.36 mm No. 8 10 to 65 10 to 65 600 um No. 30 0 to 20 0 to 20 6.1.

12、2. Type IIThe grading of Type II sodium chloride shall conform to the requirements of the purchaser to meet the needs for the intended use as noted in Section 4.1. 6.2. Condition: 6.2.1. The sodium chloride shall be delivered to the specified location in a free-flowing and usable condition. 6.2.1.1.

13、 Anticaking agents may be specified to prevent stockpiles from crusting over or forming clumps of product. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 143-3 AASHTO 6.2.1.2. The specifying age

14、ncy may establish moisture requirements in addition to the other physical requirements. 6.3. Brine: 6.3.1. Sodium chloride brine shall be delivered at a solution concentration of 23.3 percent by weight with a specific gravity of 1.176 when tested in accordance with ASTM D1429, Method D. Note 2Agenci

15、es may allow a variation of the required concentration when considering expected minimum roadway temperatures and performance needs based on the phase diagram shown in Figure X1.1. 7. SAMPLING AND TESTING 7.1. Sampling Solid Forms of Sodium Chloride: 7.1.1. Lot size shall be as agreed upon between t

16、he purchaser and supplier at the time of purchase. 7.1.2. Samples shall be taken at the point of delivery. 7.1.3. A minimum of three samples shall be randomly selected from each lot to form a representative composite sample. 7.1.4. Each increment of the composite sample shall be obtained by removing

17、 a minimum of 25 mm 1 in. of material from the surface and obtaining a 500-g approximately 1-lb sample of sodium chloride to a depth of at least 150 mm 6 in. A sampling tube, sampling thief, or other method that will ensure a representative cross section of the material shall be used. A representati

18、ve composite sample of the lot shall be the result of thoroughly combining and mixing the individual increments. 7.2. Testing shall comply with the requirements of ASTM E534, unless otherwise specified. 7.3. Rapid methods of analysis may be used to perform quality control or approval testing when pe

19、rmitted by the purchaser and the variability of the source is known. 7.4. Two additional samples shall be taken and tested as described by Sections 7.1 and 7.2, in the event of an initial sample failure of the lot. If both additional samples meet the specification requirements, the lot shall be acce

20、pted. 7.5. Sampling Sodium Chloride Brine: 7.5.1. A minimum of three samples shall be selected from each storage tank or truck to form a composite sample. 7.6. Testing the composite sample of brine shall be in accordance with ASTM D1429, Method D. 8. REJECTION 8.1. Sodium chloride that fails to conf

21、orm to the requirements of this specification may be rejected. Sodium chloride that is not free-flowing, becomes caked, or is otherwise contaminated may also be rejected, whether it has been tested or not. 2015 by the American Association of State Highway and Transportation Officials.All rights rese

22、rved. Duplication is a violation of applicable law.TS-4c M 143-4 AASHTO 8.2. Sodium chloride brine containing clumps of solid sodium chloride that have not gone into solution or other solid contaminants may be rejected. 9. CERTIFICATION 9.1. When specified in the purchase order or contract, a suppli

23、ers certification shall be provided stating that representative samples have been inspected and tested in accordance with this specification and have been found to meet the requirements of the material described in the order. When specified in the purchase order or contract, a report of the test res

24、ults shall be provided. 10. PACKAGING AND MARKING 10.1. Sodium chloride in solid form shall be delivered in bags or other containers acceptable to the purchaser. Bulk lots may also be acceptable to the purchaser. 10.2. Each container, tank, or package of sodium chloride shall be identified by the fo

25、llowing, unless otherwise specified in the purchase order or contract: 10.2.1. Manufacturers name, 10.2.2. Product name, and 10.2.3. Net weight. 10.3. Sodium chloride brine shall include the identification in Section 10.2 for the product prior to it being mixed into brine. 11. KEYWORDS 11.1. Brine;

26、sodium chloride; deicing salts; stabilization. APPENDIX (Nonmandatory Information) X1. PRODUCTION OF BRINE USING SODIUM CHLORIDE X1.1. Brine is defined as a liquid that is saturated or nearly full of chloride. X1.2. Sodium chloride brine is available commercially, and some agencies are producing bri

27、ne on site using either commercially available production systems or agency-constructed systems. X1.3. The desired concentration of sodium chloride brine that reflects the lowest freezing point of the solution is 23.3 percent. Figure X1.1 exhibits the phase diagram of sodium chloride brine and the n

28、arrow range of effectiveness as the concentration varies from the optimum. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c M 143-5 AASHTO Figure X1.1Phase Diagram of Sodium Chloride and Calcium Chl

29、oride Brine X1.4. Sodium chloride brine concentration can be adjusted during production by either dilution or reprocessing through the mixing operation to achieve the desired concentration. X1.5. FHWA-RD-95-202, Manual of Practice for an Effective Anti-Icing Program, provides detailed information ab

30、out the production of brines. X1.6. Some agencies include requirements for the addition of a corrosion inhibitor to the brine. X2. MOISTURE X2.1. The moisture determination in ASTM E534 may not be appropriate for moisture contents above 0.04 percent. X2.2. ASTM D2216, Method B, may provide more accu

31、rate moisture content for sodium chloride with higher moisture contents. X2.2.1. The drying time may vary and the method relies on the judgment of the technician to determine when a constant weight is achieved. X2.2.2. Method B more accurately represents the typical particle size for sodium chloride. X2.3. Some agencies may establish moisture requirements in addition to the other physical requirements included in Section 6. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.