1、Standard Specification for Aggregate for Masonry Mortar AASHTO Designation: M 45-151ASTM 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 Specification for Aggregate fo
2、r Masonry Mortar AASHTO Designation: M 45-151ASTM 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 DOCUMENTS 2.1. AASHTO Standards: M 6, Fine Aggregate for Hydraulic
3、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, Effect of Organic Impurities in Fine Aggregate on Strength of
4、 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 2.2. ASTM Standard: C270, Standard Specification for Mortar for Unit
5、 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 air-cooled iron blast-furnace slag specially processed to ensure suitable particle shape as well as gradation. Not
6、e 1Care should be taken to ensure a suitable particle shape, since excessive quantities of flat and elongated particles have historically caused problems with workability. 4. GRADING 4.1. Aggregate for use in masonry mortar shall be graded within the following limits, depending upon whether natural
7、sand or manufactured sand is to be used. (See Table 1.) 2015 by the 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
8、Sand 4.75 mm (No. 4) 100 100 2.36 mm (No. 8) 95 to 100 95 to 100 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 4.2. The aggregate shall not have more than 50 percent retained bet
9、ween any two consecutive sieves of those listed in Section 4.1, and no more than 25 percent between the 300-m (No. 50) and 150-m (No. 100) sieve. 4.3. 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 unle
10、ss suitable adjustments are made in proportions to compensate for the change in grading. Note 2For 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. 4.4. When an aggregate fails
11、the gradation limits specified in Sections 4.1 and 4.2, it may be 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 SubstancesTh
12、e amount of deleterious substances in aggregate for masonry mortar, 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 0.5ali
13、quid having a specific gravity of 2.0 aThis requirement does not 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 produ
14、cing a color darker than the standard shall be rejected. 5.2.2. 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
15、that, when tested for the effect of organic impurities on strength of mortar by T 71, the relative strength at seven days is not less than 95 percent. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1
16、c M 45-3 AASHTO 6. SOUNDNESS 6.1. Except as herein provided, aggregate 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
17、or 15 percent when magnesium sulfate is used. 6.2. Aggregate failing 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 perio
18、d of more than five years without appreciable disintegration. 7. 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) Sie
19、veT 11, 7.1.4. Organic ImpuritiesT 21, 7.1.5. Effect of Organic Impurities on StrengthT 71, 7.1.6. Clay Lumps and Friable ParticlesT 112, 7.1.7. Lightweight ConstituentsT 113, and 7.1.8. SoundnessT 104. 7.1.9. DensityDetermine the bulk specific gravity (oven dry basis) of the fine aggregate in accor
20、dance with T 84. The specific gravity equals the density expressed in units of g/cm3. The density of the fine aggregate in g/cm3is used in the calculation of the air content of the mortars, as required by ASTM C270. 1 Except for Sections 5.1 and 7.1.6, this specification is identical to ASTM C144-11. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
