AASHTO M 45-2016 Standard Specification for Aggregate for Masonry Mortar.pdf

1、Standard Specification for Aggregate for Masonry Mortar AASHTO Designation: M 45-161Release: Group 3 (August 2016) ASTM Designation: C144-11 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1c M 45-1 AASHTO Standard

2、 Specification for Aggregate for Masonry Mortar AASHTO Designation: M 45-161Release: Group 3 (August 2016) ASTM Designation: C144-11 1. SCOPE 1.1. This specification covers aggregate for use in masonry mortar. 1.2. The values stated in SI units are to be regarded as the standard. 2. REFERENCED DOCUM

3、ENTS 2.1. AASHTO Standards: M 6, Fine Aggregate for Hydraulic Cement Concrete T 2, Sampling of Aggregates T 11, Materials Finer Than 75-m (No. 200) Sieve in Mineral Aggregates by Washing T 21, Organic Impurities in Fine Aggregates for Concrete T 27, Sieve Analysis of Fine and Coarse Aggregates T 71,

4、 Effect of Organic Impurities in Fine Aggregate on Strength of Mortar T 84, Specific Gravity and Absorption of Fine Aggregate T 104, Soundness of Aggregate by Use of Sodium Sulfate or Magnesium Sulfate T 112, Clay Lumps and Friable Particles in Aggregate T 113, Lightweight Pieces in Aggregate T 304,

5、 Uncompacted Void Content of Fine Aggregate 2.2. ASTM Standard: C270, Standard Specification for Mortar for Unit Masonry 3. MATERIAL 3.1. Aggregate for use in masonry mortar shall consist of natural sand or manufactured sand. Manufactured sand is the product obtained by crushing stone, gravel, or ai

6、r-cooled iron blast-furnace slag specially processed to ensure suitable particle shape as well as gradation. 4. GRADING 4.1. Aggregate for use in masonry mortar shall be graded within the following limits, depending on whether natural sand or manufactured sand is to be used. (See Table 1.) 2016 by t

7、he American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-1c M 45-2 AASHTO Table 1Aggregate Grading Limits % Passing Sieve Size Natural Sand Manufactured Sand 4.75 mm (No. 4) 100 100 2.36 mm (No. 8) 95 to 100 95 to 100

8、 1.18 mm (No. 16) 70 to 100 70 to 100 600 m (No. 30) 40 to 75 40 to 75 300 m (No. 50) 10 to 35 20 to 40 150 m (No. 100) 2 to 15 10 to 25 75 m (No. 200) 0 to 5.0 0 to 10 4.3. The aggregate shall not have more than 50 percent retained between any two consecutive sieves of those listed in Section 4.1,

9、and no more than 25 percent between the 300-m (No. 50) and 150-m (No. 100) sieve. 4.4. If the fineness modulus varies by more than 0.20 from the value assumed in selecting proportions for the mortar, the aggregate shall be rejected unless suitable adjustments are made in proportions to compensate fo

10、r the change in grading. Note 1For heavy construction employing joints thicker than 12.5 mm (1/2in.), a coarser aggregate may be desirable. For such work, a fine aggregate conforming to M 6 is satisfactory. 4.5. When an aggregate fails the gradation limits specified in Sections 4.1 and 4.2, it may b

11、e used provided the mortar can be prepared to comply with the aggregate ratio, water retention, air content, and compressive strength requirements of the property specifications of ASTM C270. 5. COMPOSITION 5.1. Deleterious SubstancesThe amount of deleterious substances in aggregate for masonry mort

12、ar, each determined on independent samples complying with the grading requirements of Section 4, shall not exceed the following: Item Max Permissible Mass, % Clay lumps and friable particles 1.0 Lightweight particles, floating on 0.5aliquid having a specific gravity of 2.0 aThis requirement does not

13、 apply to blast-furnace slag aggregate. 5.2. Organic Impurities: 5.2.1. The aggregate shall be free of injurious amounts of organic impurities. Except as herein provided, aggregates subjected to the test for organic impurities and producing a color darker than the standard shall be rejected. 5.2.2.

14、Aggregate failing in the test may be used provided that the discoloration is due principally to the presence of small quantities of coal, lignite, or similar discrete particles. 5.2.3. Aggregate failing in the test may be used provided that, when tested for the effect of organic impurities on streng

15、th of mortar by T 71, the relative strength at seven days is not less than 95 percent. 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-1c M 45-3 AASHTO 6. SOUNDNESS 6.1. Except as herein provided, ag

16、gregate subjected to five cycles of the soundness test shall show a loss, weighted in accordance with the grading of a sample complying with the limitations set forth in Section 4, not greater than 10 percent when sodium sulfate is used or 15 percent when magnesium sulfate is used. 6.2. Aggregate fa

17、iling to meet the requirements of Section 6.1 may be accepted, provided that mortar of comparable properties made from similar aggregates from the same source has been exposed to weathering, similar to that to be encountered, for a period of more than five years without appreciable disintegration. 7

18、. METHODS OF SAMPLING AND TESTING 7.1. Sample and test the aggregate in accordance with the following procedures: 7.1.1. SamplingT 2; 7.1.2. Sieve Analysis and Fineness ModulusT 27; 7.1.3. Amount of Material Finer Than 75-m (No. 200) SieveT 11; 7.1.4. Organic ImpuritiesT 21; 7.1.5. Effect of Organic

19、 Impurities on StrengthT 71; 7.1.6. Clay Lumps and Friable ParticlesT 112; 7.1.7. Lightweight ConstituentsT 113; 7.1.8. SoundnessT 104; and 7.1.9. Uncompacted Void ContentT 304. 7.1.10. WorkabilityExcessive quantities of flat and elongated particles have historically caused problems with workability

20、. When measured on any aggregate of a known grading, void content provides an indication of that aggregates angularity, sphericity, and surface texture compared with other fine aggregates tested in the same grading. When void content is measured on an as-received fine aggregate grading, it can be an

21、 indicator of the effect of the fine aggregate on the workability of a mixture in which it may be used. 7.1.11. DensityDetermine the bulk specific gravity (oven dry basis) of the fine aggregate in accordance with T 84. The specific gravity equals the density expressed in units of g/cm3. The density

22、of the fine aggregate in g/cm3is used in the calculation of the air content of the mortars, as required by ASTM C270. 8. KEYWORDS 8.1. Aggregate requirements; fine aggregate; masonry mortar sand. 1 This specification is technically identical to ASTM C144-11. 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.