1、Standard Specification for High-Reactivity Pozzolans for Use in Hydraulic-Cement Concrete, Mortar, and Grout AASHTO Designation: M 321-04 (2012) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-3b M 321-1 AASHTO Sta
2、ndard Specification for High-Reactivity Pozzolans for Use in Hydraulic-Cement Concrete, Mortar, and Grout AASHTO Designation: M 321-04 (2012) 1. SCOPE 1.1. This specification covers high-reactivity pozzolans for use as a mineral admixture in portland cement concrete and mortar to fill small voids an
3、d/or where pozzolanic action is desired. High-reactivity pozzolans are microsilica products with a particle size typically one to two orders of magnitude smaller than portland cement. These materials are usually supplied in undensified or densified dry form. If the material is supplied in a densifie
4、d form, the tests should be performed on the as-collected undensified material before being processed into densified form. 1.2. The values stated in SI units are to be regarded as the standard. 1.3. This standard does not purport to address all of the safety concerns, if any, associated with its use
5、. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. Read the material safety data sheets for materials used. This standard is not intended for specifying silica fume as
6、 defined in Section 3.3. It is recommended that M 307 or ASTM C1240 be used for that purpose. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 307, Silica Fume Used in Cementitious Mixtures T 105, Chemical Analysis of Hydraulic Cement 2.2. ASTM Standards: C109/C109M, Standard Test Method for Compres
7、sive Strength of Hydraulic Cement Mortars (Using 2-in. or 50-mm Cube Specimens) C185, Standard Test Method for Air Content of Hydraulic Cement Mortar C311/C311M, Standard Test Methods for Sampling and Testing Fly Ash or Natural Pozzolans for Use in Portland-Cement Concrete C441/C441M, Standard Test
8、Method for Effectiveness of Pozzolans or Ground Blast-Furnace Slag in Preventing Excessive Expansion of Concrete Due to the Alkali-Silica Reaction C1012/C1012M, Standard Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution C1240, Standard Specification for Silica F
9、ume Used in Cementitious Mixtures 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b M 321-2 AASHTO 3. TERMINOLOGY 3.1. pozzolana siliceous or siliceous and aluminous material that in itself possesses
10、 little or no cementitious value but that will, in finely divided form and in the presence of moisture, chemically react with calcium hydroxide at ordinary temperatures to form compounds possessing cementitious properties. 3.2. high-reactivity pozzolanan amorphous silica of high silica content and p
11、urity possessing high pozzolanic activity, meeting the requirements of this standard specification. Note 1Materials such as metakaolin, rice hull ash, zirconium fume, ultrafine fly ash, and fume from the production of 50 percent ferrosilicon (with SiO2less than 85 percent) are examples of high-react
12、ivity pozzolans. 3.3. silica fumea very fine pozzolanic material composed mostly of amorphous silica produced by electric arc furnaces as a by-product of the production of elemental silicon or ferro silicon alloys (also known as condensed silica fume and microsilica), meeting the requirements of M 3
13、07 and ASTM C1240. 4. ORDERING INFORMATION 4.1. Orders for material meeting this specification shall include the following information as necessary to adequately describe the desired product: 4.1.1. Name of material (high-reactivity pozzolan material); 4.1.2. AASHTO designation and year of issue; 4.
14、1.3. Applicable optional chemical and/or physical requirements; and 4.1.4. Product formdensified or undensified in kg/m3(lb/ft3)dry. 5. CHEMICAL REQUIREMENTS 5.1. High-reactivity pozzolan shall conform to the chemical requirements prescribed in Table 1. Optional chemical requirements are shown in Ta
15、ble 2. Table 1Chemical Requirements Reactive Oxides (SiO2+ Al2O3+ Fe2O3), min percent 75.0 Sulfur trioxide (SO3), max percent 3.0 Loss on ignition, max percent 6.0 Moisture content, max percent 3.0 Table 2Optional Chemical RequirementsaAvailable alkalies, as Na2O, max percentb Report value only % ba
16、Optional chemical requirements will be made only at the request of the purchaser. bApplicable only when specifically required for mineral admixture to be used in concrete containing reactive aggregate and cement to meet a limitation on content of alkalies. 2015 by the American Association of State H
17、ighway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b M 321-3 AASHTO 6. PHYSICAL REQUIREMENTS 6.1. High-reactivity pozzolan shall conform to the physical requirements prescribed in Table 3. Optional physical requirements are shown in Table 4. Tab
18、le 3Physical Requirements Accelerated Pozzolanic Strength Activity Index: With portland cement, as percent of control, determine at 7 days 85 Fineness: max percent retained on the 45-m (No. 325) sievea10 aExercise care to avoid retaining agglomerations of extremely fine materials. Table 4Optional Ph
19、ysical RequirementsaIncrease of drying shrinkage of mortar bars at 28 days, max, percent 0.10 Uniformity requirements: In addition, when air-entrained concrete is specified, the quantity of air-entraining admixture required to produce an air content volume of 18 percent of the mortar shall not vary
20、from the average established by the 10 preceding tests, or by all preceding tests if less than 10, by more than, percent 20 Reactivity with cement alkalies: Reduction of mortar expansion at 14 days, min, percentb80 Sulfate expansion 14 days, max, percent 0.045 Pozzolanic Strength Activity Index (non
21、accelerated curing): With portland cement, as percent of control, determined at 28 days 100 a Optional physical requirements will be made only at the request of the purchaser.b The indicated tests for reactivity with cement alkalies in accordance with ASTM C441/C441M should not be requested unless t
22、he material is to be used with an aggregate that is regarded as deleteriously reactive with alkalies in cement. The test for reduction of mortar expansion may be made using any high-alkali cement in accordance with ASTM C441/C441M if the portland cement to be used in the mix is not known or is not a
23、vailable at the time of the test. 7. METHODS OF SAMPLING AND TESTING 7.1. High-reactivity pozzolan shall be sampled at the purchasers option in accordance with ASTM C311/C311M. 7.2. Testing of the high-reactivity pozzolan in accordance with the requirements of Section 8 shall be conducted at the opt
24、ion of the purchaser. 8. TEST METHODS 8.1. Chemical Analysis: 8.1.1. Silicon Dioxide, Aluminum Oxide, Iron Oxide, and Sulfur TrioxideDetermine in accordance with T 105 for pozzolans with insoluble residue greater than 1 percent. Rapid test methods referenced in T 105 may be used. 8.1.2. Moisture Con
25、tent, Loss on Ignition, and Available AlkaliesMake these determinations following applicable provisions of ASTM C311/C311M. 8.2. Physical Tests: 8.2.1. DensityASTM C311/C311M, record only. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication
26、 is a violation of applicable law.TS-3b M 321-4 AASHTO 8.2.2. Increase of Drying Shrinkage of Mortar BarsASTM C311/C311M, except use 500 g of portland cement, 50 g of high-reactivity pozzolan, and 1325 g of sand in test mixture. The 50 g of high-reactivity pozzolan replaces the 125 g of mineral admi
27、xture prescribed in ASTM C311/C311M. 8.2.3. Reactivity with Cement AlkaliesASTM C441/C441M, except that the amount of high-reactivity pozzolan in the test mixture shall be 10 percent by mass of cementitious material. 8.2.4. Accelerated Pozzolanic Strength Activity Index with Portland CementASTM C311
28、/C311M, with the procedure as modified in M 307 or ASTM C1240, Section 16. A set of samples shall be evaluated at 7 days of age. As an optional test, use Pozzolanic Strength Activity Index with Portland Cement, ASTM C311/C311M, with the procedure as modified in M 307 or ASTM C1240, Section 16, excep
29、t with curing on a nonaccelerated basis as in ASTM C109/C109M. A set of samples shall be evaluated at 28 days of age. 8.2.5. Air-Entrainment of MortarASTM C311/C311M, except use 300 g of portland cement, 30 g of high-reactivity pozzolan, and 1170 g of standard Ottawa sand in the test mixture. Use su
30、fficient water, mL, to give a flow of 80 to 95 percent and sufficient neutralized Vinsol resin solution, mL, to produce an air content of 18 3 percent. 8.2.6. Also, use the following equation for Wc: ( )( )300 1170 30 300 0.01300 3.15 1170 2.65 30 300 0.01 1cPWDP+ + + =+ + + (1) 8.2.7. Then calculat
31、e: air content, volume % = 1001 (Wa/Wc)Wa= W/400 (2) where: Wa= actual mass per unit of volume of mortar as determined by ASTM C185, g/mL, W = mass of the specified 400 mL of mortar (see Test Method ASTM C185), g, Wc= theoretical mass per unit volume, calculated on an air-free basis and using the va
32、lues for density and quantities in the material in the mixture, g/mL, P = percent passing of mixing water plus Vinsol resin solution based on mass of cement, and D = density of silica fumes used in the mixture, Mg/m3. 8.2.7.1. Sulfate ExpansionASTM C1012/C1012M, except that the amount of high-reacti
33、vity pozzolan in the test mixture shall be 10 percent by mass of cementitious material. 9. STORAGE AND INSPECTION 9.1. The high-reactivity pozzolan shall be stored in such a manner as to permit easy access for proper inspection and identification. Every facility shall provide the purchaser access fo
34、r sampling and inspection, either at the source or at the site of the work. 10. REJECTION 10.1. Materials that fail to conform to the requirements of this specification shall be rejected. Rejections shall be reported to the producer or supplier promptly. 2015 by the American Association of State Hig
35、hway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b M 321-5 AASHTO 11. CERTIFICATION 11.1. Upon request of the purchaser in the contract or order, a manufacturers certification shall be furnished stating the results of tests made on samples of th
36、e material taken during production or transfer and indicating conformance with applicable requirements of this specification. Information on incorporated admixtures shall also be required. 12. PACKAGING AND PACKAGE MARKING 12.1. When high-reactivity pozzolan is delivered in packages, the name and br
37、and of the manufacturer, the loose bulk density, manufacturing lot number (incorporating manufacturing date), and the mass of the high-reactivity pozzolan contained therein shall be clearly marked on each package/pallet. Similar information shall be provided in the shipping invoices accompanying the shipment of the high-reactivity pozzolan. All packages shall be in good condition at the time of delivery. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
