1、Standard Method of Test for Materials Finer Than 75-m (No. 200) Sieve in Mineral Aggregates by Washing AASHTO Designation: T 11-05 (2013)1ASTM Designation: C117-13 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1c
2、 T 11-1 AASHTO Standard Method of Test for Materials Finer Than 75-m (No. 200) Sieve in Mineral Aggregates by Washing AASHTO Designation: T 11-05 (2013)1ASTM Designation: C117-13 1. SCOPE 1.1. This test method covers determination of the amount of material finer than a 75-m (No. 200) sieve in aggreg
3、ate by washing. Clay particles and other aggregate particles that are dispersed by the wash water, as well as water-soluble materials, will be removed from the aggregate during the test. 1.2. Two procedures are included, one using only water for the washing operation, and the other including a wetti
4、ng agent to assist the loosening of the material finer than the 75-m (No. 200) sieve from the coarser material. Unless otherwise specified, Procedure A (water only) shall be used. 1.3. The values stated in SI units are to be regarded as the standard. 1.4. This standard may involve hazardous material
5、s, 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 establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to us
6、e. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 92, Wire-Cloth Sieves for Testing Purposes M 231, Weighing Devices Used in the Testing of Materials T 2, Sampling of Aggregates T 27, Sieve Analysis of Fine and Coarse Aggregates T 248, Reducing Samples of Aggregate to Testing Size 2.2. ASTM Standa
7、rds: C117, Standard Test Method for Materials Finer than 75-m (No. 200) Sieve in Mineral Aggregates by Washing C670, Standard Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials 3. SUMMARY OF METHOD 3.1. A sample of the aggregate is washed in a prescribed
8、 manner, using either plain water or water containing a wetting agent, as specified. The decanted wash water, containing suspended and 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 11-2 AASHTO
9、dissolved material, is passed through a 75-m (No. 200) sieve. The loss in mass resulting from the wash treatment is calculated as mass percent of the original sample and is reported as the percentage of material finer than a 75-m (No. 200) sieve by washing. 4. SIGNIFICANCE AND USE 4.1. Material fine
10、r than the 75-m (No. 200) sieve can be separated from larger particles much more efficiently and completely by wet sieving than through the use of dry sieving. Therefore, when accurate determinations of material finer than 75 m in fine or coarse aggregate are desired, this test method is used on the
11、 sample prior to dry sieving in accordance with T 27. The results of this test method are included in the calculation in T 27, and the total amount of material finer than 75 m by washing, plus that obtained by dry sieving the same sample, is reported with the results of T 27. Usually the additional
12、amount of material finer than 75 m obtained in the dry-sieving process is a small amount. If it is large, the efficiency of the washing operation should be checked. A large amount of material could also be an indication of the degradation of the aggregate. 4.2. Plain water is adequate to separate th
13、e material finer than 75 m from the coarser material with most aggregates. In some cases, the finer material is adhering to the larger particles, such as some clay coatings and coatings on aggregates that have been extracted from bituminous mixtures. In these cases, the fine material will be separat
14、ed more readily with a wetting agent in the water. 5. APPARATUS AND MATERIALS 5.1. BalanceThe balance shall have sufficient capacity, be readable to 0.1 percent of the sample mass, or better, and conform to the requirements of M 231. 5.2. SievesA nest of two sieves, the lower being a 75-m (No. 200)
15、sieve and the upper being a sieve with openings in the range of 2.36 mm (No. 8) to 1.18 mm (No. 16), both conforming to the requirement of M 92. 5.3. ContainerA pan or vessel of a size sufficient to contain the sample covered with water and to permit vigorous agitation without loss of any part of th
16、e sample or water. 5.4. OvenAn oven of sufficient size, capable of maintaining a uniform temperature of 110 5C (230 9F). 5.5. Wetting AgentAny dispersing agent, such as liquid dishwashing detergents, that will promote separation of the fine materials. Note 1The use of a mechanical apparatus to perfo
17、rm the washing operation is not precluded, provided the results are consistent with those obtained using manual operations. The use of some mechanical washing equipment with some samples may cause degradation of the sample. 6. SAMPLING 6.1. Sample the aggregate in accordance with T 2. If the same te
18、st sample is to be tested for sieve analysis according to T 27, comply with the applicable requirements of that method. 6.2. Thoroughly mix the sample of aggregate to be tested and reduce the quantity to an amount suitable for testing using the applicable methods described in T 248. If the same test
19、 sample is to be tested according to T 27, the minimum mass shall be as described in the applicable sections of that method. Otherwise, the mass of the test sample, after drying, shall conform with the following: 2015 by the American Association of State Highway and Transportation Officials.All righ
20、ts reserved. Duplication is a violation of applicable law.TS-1c T 11-3 AASHTO Nominal Maximum Size Minimum Mass, g 4.75 mm (No. 4) or smaller 300 9.5 mm (3/8in.) 1000 19.0 mm (3/4in.) 2500 37.5 mm (11/2in.) or larger 5000 The test sample shall be the end result of the reduction. Reduction to an exac
21、t predetermined mass shall not be permitted. If the nominal maximum size of the aggregate to be tested is not listed above, the next larger size listed shall be used to determine sample size. 7. SELECTION OF PROCEDURE 7.1. Procedure A shall be used, unless otherwise specified by the specification wi
22、th which the test results are to be compared, or when directed by the agency for which the work is performed. 8. PROCEDURE AWASHING WITH PLAIN WATER 8.1. Dry the test sample to constant mass at a temperature of 110 5C (230 9F). Determine the mass to the nearest 0.1 percent of the mass of the test sa
23、mple. 8.2. If the applicable specification requires that the amount passing the 75-m (No. 200) sieve shall be determined on a portion of the sample passing a sieve smaller than the nominal maximum size of the aggregate, separate the sample on the designated sieve and determine the mass of the materi
24、al passing the designated sieve to 0.1 percent of the mass of this portion of the test sample. Use this mass as the original dry mass of the test sample in Section 10.1. Note 2Some specifications for aggregates with a nominal maximum size of 50 mm or greater, for example, provide a limit for materia
25、l passing the 75-m (No. 200) sieve determined on that portion of the sample passing the 25.0-mm sieve. Such procedures are necessary because it is impractical to wash samples of the size required when the same test sample is to be used for sieve analysis by T 27. 8.3. After drying and determining th
26、e mass, place the test sample in the container and add sufficient water to cover it. No detergent, dispersing agent, or other substance shall be added to the water. Agitate the sample with sufficient vigor to result in complete separation of all particles finer than the 75-m (No. 200) sieve from the
27、 coarser particles, and to bring the fine material into suspension. The use of a large spoon or other similar tool to stir and agitate the aggregate in the wash water has been found satisfactory. Immediately pour the wash water containing the suspended and dissolved solids over the nested sieves, ar
28、ranged with the coarser sieve on top. Take care to avoid, as much as feasible, the decantation of coarser particles of the sample. 8.4. Add a second charge of water to the sample in the container, agitate, and decant as before. Repeat this operation until the wash water is clear. Note 3If mechanical
29、 washing equipment is used, the charging of water, agitating, and decanting may be a continuous operation. Note 4A spray nozzle or a piece of rubber tubing attached to a water faucet may be used to rinse any of the material that may have fallen onto the sieves. The velocity of water, which may be in
30、creased by pinching the tubing or by use of a nozzle, should not be sufficient to cause any splashing of the sample over the sides of the sieve. 8.5. Return all material retained on the nested sieves by flushing to the washed sample. Dry the washed aggregate to constant mass at a temperature of 110
31、5C (230 9F) and determine the mass to the nearest 0.1 percent of the original mass of the sample. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 11-4 AASHTO Note 5Following the washing of the sa
32、mple and flushing any materials retained on the 75-m (No. 200) sieve back into the container, no water should be decanted from the container except through the 75-m sieve, to avoid loss of material. Excess water from flushing should be evaporated from the sample in the drying process. 9. PROCEDURE B
33、WASHING USING A WETTING AGENT 9.1. Prepare the sample in the same manner as for Procedure A. 9.2. After drying and determining the mass, place the test sample in the container. Add sufficient water to cover the sample, and add wetting agent to the water (Note 6). Agitate the sample with sufficient v
34、igor to result in complete separation of all particles finer than the 75-m (No. 200) sieve from the coarser particles, and to bring the fine material into suspension. The use of a large spoon or other similar tool to stir and agitate the aggregate in the wash water has been found satisfactory. Immed
35、iately pour the wash water containing the suspended and dissolved solids over the nested sieves, arranged with the coarser sieve on top. Take care to avoid, as much as feasible, the decantation of coarser particles of the sample. Note 6There should be enough wetting agent to produce a small amount o
36、f suds when the sample is agitated. The quantity will depend on the hardness of the water and the quality of the detergent. Excessive suds may overflow the sieves and carry some material with them. 9.3. Add a second charge of water (without wetting agent) to the sample in the container, agitate, and
37、 decant as before. Repeat this operation until the wash water is clear. 9.4. Complete the test as for Procedure A. 10. CALCULATION 10.1. Calculate the amount of material passing a 75-m (No. 200) sieve by washing as follows: ( )/ 100A BC B=(1) where: A = percentage of material finer than a 75-m (No.
38、200) sieve by washing; B = original dry mass of sample, g; and C = dry mass of sample after washing, g. 11. REPORT 11.1. Report the percentage of material finer than the 75-m (No. 200) sieve by washing to the nearest 0.1 percent, except if the result is 10 percent or more, report the percentage to t
39、he nearest whole number. 11.2. Include a statement as to which procedure was used. 12. PRECISION AND BIAS 12.1. PrecisionThe estimates of precision of this test method listed in Table 1 are based on results from the AASHTO Materials Reference Laboratory Proficiency Sample Program, with testing condu
40、cted by this test method and ASTM C117. The significant differences between the methods at the time the data were acquired is that T 11 required, and ASTM C117 prohibited, the use of a 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is
41、a violation of applicable law.TS-1c T 11-5 AASHTO wetting agent. The data are based on the analyses of more than 100 paired test results from 40 to 100 laboratories. Table 1Precision Standard Deviation (1s),a% Acceptable Range of Two Results (d2s),a% Coarse aggregate:bSingle-operator precision 0.10
42、0.28 Multilaboratory precision 0.22 0.62 Fine aggregate:cSingle-operator precision 0.15 0.43 Multilaboratory precision 0.29 0.82 a These numbers represent the (1s) and (d2s) limits as described in ASTM C670. b Precision estimates are based on aggregates having a nominal maximum size of 19.0 mm (3/4i
43、n.) with less than 1.5 percent finer than the 75-m (No. 200) sieve. c Precision estimates are based on fine aggregates having 1.0 to 3.0 percent finer than the 75-m (No. 200) sieve. 12.1.1. The precision values for fine aggregate in Table 1 are based on nominal 500-g test samples. Revision of this t
44、est method in 1996 permits the fine aggregate test sample size to 300-g minimum. Analysis of results of testing of 300-g and 500-g test samples from Aggregate Proficiency Test Samples 99 and 100 (Samples 99 and 100 were essentially identical) produced the precision values in Table 2, which indicates
45、 only minor differences due to test sample size. Table 2Precision Data for 300-g and 500-g Test Samples Fine Aggregate Proficiency Sample Within Laboratory Between Laboratory Test Result Sample Size No. Labs Avg 1s d2s 1s d2s AASHTO T 11/ASTM C117 (Total material passing the 500 g 270 1.23 0.08 0.24
46、 0.23 0.66 No. 200 sieve by washing, %) 300 g 264 1.20 0.10 0.29 0.24 0.68 Note 7The values for fine aggregate in Table 1 will be revised to reflect the 300-g test sample size when a sufficient number of Aggregate Proficiency Tests have been conducted using that sample size to provide reliable data.
47、 12.2. BiasBecause there is no accepted reference material suitable for determining the bias for the procedure in this test method, no statement on bias is made. 13. KEYWORDS 13.1. Aggregate; size analysis; wash loss; 75-m (No. 200) sieve. 1 Except for Sections 5.1 and 6.2, and Note 4, this test method is identical with ASTM C117-13. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
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