AASHTO T 112-2000 Standard Method of Test for Clay Lumps and Friable Particles in Aggregate《集料中的土块和易碎颗粒含量的测试方法》.pdf

1、Standard Method of Test for Clay Lumps and Friable Particles in Aggregate AASHTO Designation: T 112-00 (2012)1ASTM Designation: C142-97 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1c T 112-1 AASHTO Standard Met

2、hod of Test for Clay Lumps and Friable Particles in Aggregate AASHTO Designation: T 112-00 (2012)1ASTM Designation: C142-97 1. SCOPE 1.1. This method covers the approximate determination of clay lumps and friable particles in natural aggregates. 1.2. This standard may involve hazardous materials, op

3、erations, 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 consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prio

4、r to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 6, Fine Aggregate for Hydraulic Cement Concrete M 80, Coarse Aggregate for Hydraulic Cement Concrete M 92, Wire-Cloth Sieves for Testing Purposes M 231, Weighing Devices Used in the Testing of Materials T 11, Materials Finer Than 75-m (No. 2

5、00) Sieve in Mineral Aggregates by Washing 3. SIGNIFICANCE AND USE 3.1. This test method is of primary significance in determining the acceptability of aggregate with respect to the requirements of M 6 and M 80. 4. APPARATUS 4.1. BalanceThe balance shall have sufficient capacity, be readable to 0.1

6、percent of the sample mass, or better, and conform to the requirements of M 231. 4.2. ContainersRust-resistant containers of a size and shape that will permit the spreading of the sample on the bottom in a thin layer. 4.3. SievesSieves conforming to M 92. 4.4. OvenAn oven providing free circulation

7、of air and capable of maintaining a temperature of 110 5C (230 9F). 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 112-2 AASHTO 5. SAMPLES 5.1. Aggregate for this test shall consist of the mater

8、ial remaining after completion of T 11. To provide the quantities designated in Sections 5.3 and 5.4, it may be necessary to combine material from more than one test by T 11. 5.2. Dry the aggregate to substantially constant mass at a temperature of 110 5C (230 9F). 5.3. Test samples of fine aggregat

9、e shall consist of the particles coarser than a 1.18-mm (No. 16) sieve and shall have a mass not less than 25 g. 5.4. Separate the test samples of coarse aggregate into different sizes, using the following sieves: 4.75 mm (No. 4), 9.5 mm (3/8in.), 19.0 mm (3/4in.), and 37.5 mm (11/2in.). The test sa

10、mple shall weigh not less than indicated in the following table: Size of Particles Making Up Test Sample Weight of Test Sample, Min, g 4.75 to 9.5 mm (No. 4 to 3/8in.) 1000 9.5 to 19.0 mm (3/8to 3/4in.) 2000 19.0 to 37.5 mm (3/4to 11/2in.) 3000 Over 37.5 mm (11/2in.) 5000 5.5. If the grading of the

11、original sample provides less than 5 percent of any of the sizes indicated in Section 5.4, do not test that size. 5.6. In the case of aggregate that is composed of substantial amounts of both fine and coarse aggregate sizes, separate the material into two sizes at the 4.75-mm (No. 4) sieve, and prep

12、are the samples of fine and coarse aggregate in accordance with Sections 5.3 and 5.4. Any aggregate containing 50 percent or more material retained on the 4.75-mm (No. 4) sieve is considered to be coarse aggregate. Note 1In most cases, only the plus 4.75-mm (No. 4) fraction of coarse aggregate needs

13、 to be evaluated by this test method, regardless of the amount of minus 4.75-mm (No. 4) material present. However, the amount of 1.18-mm (No. 16) to 4.75-mm (No. 4) material present shall be included in the weight of the test sample in Section 7.1 when calculating the percent of clay lumps and friab

14、le particles. 6. PROCEDURE 6.1. Determine the mass of the test sample to the accuracy specified in Section 4.1 and spread it in a thin layer on the bottom of the container, cover it with distilled water and soak it for a period of 24 4 h. Roll and squeeze particles individually between the thumb and

15、 forefinger to attempt to break the particle into smaller sizes. Do not use the fingernails to break up particles, or press particles against a hard surface or each other. Classify any particles that can be broken with the fingers into fines removable by wet sieving as clay lumps or friable particle

16、s. After all discernible clay lumps and friable particles have been broken, separate the undersized material from the remainder of the sample by wet sieving over the sieve prescribed in Table 1. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Dupli

17、cation is a violation of applicable law.TS-1c T 112-3 AASHTO Table 1Procedure Size of Particles Making Up Sample Size of Sieve for Removing Residue of Clay Lumps and Friable Particles Fine aggregate (retained on 1.18-mm (No. 16) sieve) 850 m (No. 20) 4.75 to 9.5 mm (No. 4 to 3/8in.) 2.36 mm (No .8)

18、9.5 to 19.0 mm (3/8to 3/4in.) 4.75 mm (No. 4) 19.0 to 37.5 mm (3/4to 11/2in.) 4.75 mm (No. 4) Over 37.5 mm (11/2in.) 4.75 mm (No. 4) 6.2. Perform the wet sieving by passing water over the sample through the sieve while manually agitating the sieve, until all undersize material has been removed. 6.3.

19、 Remove the retained particles carefully from the sieve, dry to substantially constant mass at a temperature of 110 5C (230 9F), allow to cool, and determine the mass to the accuracy specified in Section 4.1. 7. CALCULATION 7.1. Calculate the percent of clay lumps and friable particles in fine aggre

20、gate or individual sizes of coarse aggregate as follows: ( ) 100P M RM=(1) where: P = percent of clay lumps and friable particles; M = mass of test sample (for fine aggregate the mass of the portion coarser than the 1.18-mm (No. 16) sieve as described in Section 5.3); and R = mass of particles retai

21、ned on designated sieve, as determined in accordance with Section 6.3. 7.2. For coarse aggregates, the percent of clay lumps and friable particles shall be an average based on the percent of clay lumps and friable particles in each sieve-size fraction weighted in accordance with the grading of the o

22、riginal sample before separation, or, preferably, the average grading of the supply represented by the sample. For the purpose of calculating the weighted average when the sample contains less than 5 percent of the material in a given size, that size shall be considered to contain the same percent o

23、f clay lumps and friable particles as the next larger or next smaller size, whichever is present. 8. PRECISION AND BIAS 8.1. PrecisionThe estimate of the precision of this test method is provisional and is based on samples of one fine aggregate that was tested by ten different operators at nine diff

24、erent laboratories. For that sample, the average “percent of clay lumps and friable particles” in the aggregate was 1.2 percent, and the standard deviation was 0.6 percent. Based on this standard deviation, the acceptable range of two test results on samples from the same aggregate sent to different

25、 laboratories is 1.7 percent. 8.2. BiasBecause there is no acceptable reference material for determining the bias for the procedure in this test method, no statement is being made. 1Except for Sections 4.1 and 5.6, this method is identical to ASTM C142-97. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.