1、Standard Method of Test for Soundness of Aggregates by Freezing and Thawing AASHTO Designation: T 103-08 (2012) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1c T 103-1 AASHTO Standard Method of Test for Soundnes
2、s of Aggregates by Freezing and Thawing AASHTO Designation: T 103-08 (2012) 1. SCOPE 1.1. This method describes three procedures to be followed in testing aggregates to determine their resistance to disintegration by freezing and thawing. It furnishes information helpful in judging the soundness of
3、aggregates subjected to weathering, particularly when adequate information is not available from service records of the behavior of the aggregate. 1.2. The following applies to all specified limits in this standard: For the purpose of determining conformance with these specifications, an observed va
4、lue or a calculated value shall be rounded off “to the nearest unit” in the last right-hand place of figures used in expressing the limiting value, in accordance with the rounding-off method of ASTM E 29. 1.3. The values stated in SI units are to be regarded as the standard. 2. REFERENCED DOCUMENTS
5、2.1. AASHTO Standards: M 92, Wire-Cloth Sieves for Testing Purposes M 231, Weighing Devices Used in the Testing of Materials R 16, Regulatory Information for Chemicals Used in AASHTO Tests T 27, Sieve Analysis of Fine and Coarse Aggregates 2.2. ASTM Standard: E 29, Standard Practice for Using Signif
6、icant Digits in Test Data to Determine Conformance with Specifications 3. APPARATUS 3.1. The apparatus shall consist of the following: 3.1.1. Freezing EquipmentNo specific requirements for the type or size of the freezing equipment are given, as many laboratories have adequate equipment but variable
7、 in type and size. The freezing and thawing apparatus shall consist of a suitable chamber or chambers in which the sample may be subjected to the specified freezing and thawing cycle, together with the necessary refrigerating and heating equipment and controls to continuously and automatically produ
8、ce reproducible cycles within the specified temperature requirements. In the event that the equipment does not operate automatically, provision shall be made for either its continuous manual operation on a 24-hour-a- day basis or for the storage of all samples in a thawed condition when the equipmen
9、t is not in operation. All equipment shall be capable of being operated at a temperature not higher than 26 3C (15 5.4F) to 21 3C (70 5.4F) at any point in the freezing chamber. The 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a v
10、iolation of applicable law.TS-1c T 103-2 AASHTO equipment shall be equipped with an automatic temperature-recording device with an approximate temperature range of 40C (40F) to 50C (122F), readable and accurate to 0.5C (1F). 3.1.2. Sample ContainersThe sample containers shall be of plastic, rubber,
11、or other materials suitable for the procedure to be followed. The containers shall be flexible so as not to cause undue stress on the aggregate being tested in water in the freezing cycle. The sample containers shall be of sufficient size to hold the required sample and solution, as well as being co
12、mpatible with the freeze/thaw apparatus. 3.1.3. SievesThe sieves used shall meet the requirements of M 92. 3.1.4. 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. 3.1.5. Drying OvenThe drying oven s
13、hall provide a free circulation of air through the oven and shall be capable of maintaining a temperature of 110 5C (230 9F). 3.1.6. TemperatureMeasuring EquipmentShall consist of thermometers, resistance thermometers, or thermocouples, capable of measuring the temperature at various points within t
14、he testing chamber and at the centers of each sample container. The thermometers, resistance thermometers, or thermocouples shall have an approximate range from 26 to 50C (15 to 120F), readable and accurate to 0.5C (1F). 4. SAMPLES 4.1. Fine AggregateFine aggregate for the test shall be passed throu
15、gh a 9.5-mm (3/8-in.) sieve. The sample shall be of such size that it will yield a minimum 100 g of each of the following sieves: Table 1Sieve Size Passing Sieve Retained on Sieve 9.5 mm (3/8in.) 4.75 mm (No. 4) 4.75 mm (No. 4) 2.36 mm (No. 8) 2.36 mm (No. 8) 1.18 mm (No. 16) 1.18 mm (No. 16) 600 m
16、(No. 30) 600 m (No. 30) 300 m (No. 50) 4.1.1. Should the sample contain less than 5 percent of any of the sizes specified in Section 4.1, that size shall not be tested. 4.2. Coarse AggregateCoarse aggregate for the test shall consist of +4.75-mm (No. 4) sieve size material. The sample shall be of su
17、ch a size that it will yield the following minimum: Table 2Grading Requirements Fraction Size Range (Note 1) Mass, g Larger sizes by 25.0-mm (1-in.) spread in sieve size, each fraction 7000 1000 63-mm to 50-mm (21/2-in. to 2-in.) material 3000 300 50-mm to 37.5-mm (2- in. to 11/2-in.) material 2000
18、200 37.5-mm to 25.0-mm (11/2-in. to 1-in.) material 1000 50 25.0-mm to 19.0-mm (1-in. to 3/4-in.) material 700 30 19.0-mm to 12.5-mm (3/4-in. to 1/2-in.) material 670 10 12.5-mm to 9.5-mm (1/2-in. to 3/8-in.) material 330 5 9.5-mm to 4.75-mm (3/8-in. to No. 4) material 300 5 2014 by the American Ass
19、ociation of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 103-3 AASHTO Note 1The number and size range of fraction sizes, which are shown in Table 2, may be changed to reduce the number of size fractions being tested; however, th
20、e total sample mass for the number of size fractions being tested should equal the sample mass for the size as shown in Table 2. 4.3. Should the samples contain less than 5 percent of the sizes specified in Section 4.1 or 4.2, that size shall not be tested. For the purpose of calculating the test re
21、sults, it shall be considered to have the same loss in treatment as the average of the next smaller and the next larger size. If one of these sizes is absent, it shall be considered to have the same loss as the next larger or next smaller size, whichever is present. When the 19- to 9.5-mm (3/4- to 3
22、/8-in.), 37.5- to 19.0-mm (3/4- to 11/2-in.), or 63- to 37.5-mm (21/2- to 11/2-in.) test samples specified in Section 4.2 cannot be prepared due to absence of one of the two sizes of aggregate shown for each, the size available shall be used to prepare the sample tested. 4.4. When a sample is to be
23、tested with more than 10 percent coarser than the 9.5-mm (3/8-in.) sieve and, also, more than 10 percent finer than the 4.75-mm (No. 4) sieve, the sample shall be divided into a minus 4.75-mm fraction and a plus 4.75-mm fraction. The resulting fractions shall be tested in accordance with the procedu
24、res for fine aggregate and coarse aggregate, respectively. Report the results separately for the fine aggregate fraction and the coarse aggregate fraction, giving the percentages of the coarse and fine size fractions in the initial grading. Table 3Grading Requirements Size (Square-Opening Sieves) Ma
25、ss, g 9.5 mm to 4.75 mm (3/8in. to No. 4) 300 5 19.0 mm to 9.5 mm (3/4in. to 3/8in.) 1000 10 Consisting of: 12.5-mm to 9.5-mm (1/2-in. to 3/8-in.) material 330 5 19.0-mm to 12.5-mm (3/4-in. to 1/2-in.) material 670 10 37.5-mm to 19.0-mm (11/2-in. to 3/4-in.) material 1500 50 Consisting of: 25.0-mm t
26、o 19.0-mm (1-in. to 3/4-in.) material 500 30 37.5-mm to 25.0-mm (11/2-in. to 1-in.) material 1000 50 63-mm to 37.5-mm (21/2-in. to 11/2-in.) material 5000 300 Consisting of: 50-mm to 37.5-mm (2-in. to 11/2-in.) material 2000 200 63-mm to 50-mm (21/2-in. to 2-in.) material 3000 300 Larger sizes by 25
27、.0-mm (1-in.) spread in sieve size, each fraction 7000 1000 5. PREPARATION OF TEST SAMPLE 5.1. Fine AggregateThe sample shall be thoroughly washed on a 150-m (No. 100) sieve and dried to constant mass at a temperature of 110 5C (230 9F). The sample shall be separated into the different sizes by siev
28、ing, as follows: 5.1.1. Separate each fraction of mineral aggregate by sieving over the required nest of the standard sieves specified in Section 4.1. From the fractions obtained in this manner, select samples of sufficient size to yield 100 g after sieving to refusal per T 27. Fine aggregate sticki
29、ng in the meshes of the sieves shall not be used in preparing the samples. Samples consisting of 100 g shall be weighed out of each of the separated fractions after final sieving and placed in separate containers for the test. 2014 by the American Association of State Highway and Transportation Offi
30、cials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 103-4 AASHTO 5.2. Coarse AggregateThe sample of coarse aggregate shall be thoroughly washed and dried to constant mass at a temperature of 110 5C (230 9F). It shall be separated into the different sizes shown in Section
31、4.2 by sieving to refusal per T 27. The proper mass of sample for each fraction shall be weighed out and placed in separate containers for the test. In the case of fractions coarser than the 19.0-mm (3/4-in.) sieve, the number of particles shall be counted. 5.3. Ledge RockFor testing ledge rock, the
32、 sample shall be prepared by breaking it into fragments reasonably uniform in size and shape and having a mass of approximately 100 g each. The test sample shall have a mass of 5000 100 g. The sample shall be thoroughly washed and dried previous to the test as described in Section 5.2. Table 4Sugges
33、ted Form for Recording Test Data (with Illustrative Test Values) Sieve Size Grading of Original Sample, Percent Mass of Test Fractions Before Test, g Percentage Passing Designated Sieve After Test Weighted Percentage Loss Soundness Test of Fine Aggregate Minus 150 m 5 300 m to 150 m 12 600 m to 300
34、m 26 100 4.2 1.1 1.18 mm to 600 m 25 100 4.8 1.2 2.36 mm to 1.18 mm 17 100 8.0 1.4 4.75 mm to 2.36 mm 11 100 11.2 1.2 9.5 mm to 4.75 mm 4 11.2a0.4 Totals 100 5 Soundness Test of Coarse Aggregate 63 mm to 50 mm 50 mm to 37.5 mm 2825 g 1958 g 63 to 37.5 mm 20 4783 4.8 1.0 37.5 mm to 25.0 mm 25.0 mm to
35、 19.0 mm 1012 g 513 g 37.5 to 19.0 mm 45 1525 8.0 3.6 19.0 mm to 12.5 mm 12.5 mm to 9.5 mm 675 g 333 g 19.0 to 9.5 mm 23 1008 9.6 2.2 9.5 mm to 4.75 mm 12 298 11.2 1.3 Totals 100 8 The percentage loss (11.2 percent) of the next smaller size is used as the percentage loss for this size, because this
36、size contains less than 5 percent of the original sample as received. See Section 4.3. 6. PROCEDURES 6.1. Procedure ATotal Immersion: 6.1.1. Each sample fraction obtained per Section 5 shall be placed in a freeze/thaw container. Sufficient quantity of water, 3 percent NaCl and water solution, or 0.5
37、 percent methyl alcohol and water solution shall be added to the sample container to completely immerse the sample in the solution. Allow the immersed sample to soak for 24 4 h at a temperature of 23 3C (73 5F) prior to the start of the freeze cycle. 6.1.2. Each sample fraction container shall be pl
38、aced in the freeze apparatus. A thermometer or thermocouple shall be placed in the center of one of the samples. The sample shall be cooled until the temperature at the center of the sample reaches 23 3C (9 5F). The temperature shall be held for a minimum 2 h prior to the start of the thaw cycle. Up
39、on completion of a freeze cycle, the temperature at the center of the sample shall be raised to 21 3C (70 5F). The temperature shall be held for a minimum 30 min. 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applica
40、ble law.TS-1c T 103-5 AASHTO 6.2. Procedure BPartial Immersion in AlcoholWater Solution: 6.2.1. In this procedure, the samples shall be placed in a vacuum chamber and saturated by subjecting them to an air pressure of not over 3.4 kPa (25.4 mm of mercury), and breaking the vacuum with a sufficient a
41、mount of a 0.5 percent (by mass) solution of ethyl alcohol in water to completely cover the samples. The samples shall be left in the solution for 15 min. 6.2.2. The samples shall then be removed from the vacuum chamber. Coarse aggregates shall be placed one layer deep in shallow pans containing 6.4
42、 mm (1/4in.) of the alcohol-water solution and frozen in this condition. Samples of fine aggregate can most conveniently be handled by placing them in 250-m (No. 60) or finer wire cloth sieves, which in turn are held in shallow trays, and the samples frozen in a surface-wet condition. 6.2.3. Samples
43、 shall be frozen and thawed as required in Procedure A. 6.3. Procedure CPartial Immersion in Water: 6.3.1. This procedure is the same as Procedure B except that water is used instead of the alcohol-water solution. 7. CYCLES 7.1. Alternate freezing and thawing shall be repeated until the required num
44、ber of cycles is obtained. One test cycle consists of one freeze cycle and one thaw cycle. Repeat the procedure of alternate freezing and thawing for 25 cycles. Aggregate type and history may require additional cycles to accurately evaluate aggregate performance. One complete cycle shall not exceed
45、24 h. If the test is interrupted, the sample shall remain covered in a thawed state until testing is resumed. The sample shall remain immersed during the test. Some authorities have required 50, 16, and 25 cycles for Procedures A, B, and C, respectively. 8. QUANTITATIVE EXAMINATION 8.1. The quantita
46、tive examination shall be made as follows: 8.1.1. After the completion of the final cycle, each sample shall be dried to constant mass at 110 5C (230 9F), weighed, and except in the case of fine aggregate or ledge rock, sieved over the sieve shown for the appropriate size of particle in Table 4. The
47、 material retained on the sieve shall be weighed and the mass recorded. Larger sizes by 25-mm spread in sieve size shall be sieved over the original retaining sieve to determine their loss. The material retained on each sieve shall be weighed and the mass recorded. Table 5Sieve Size Size of Aggregat
48、e Sieve Used to Determine Loss 63 mm to 37.5 mm (21/2to 11/2in.) 31.5 mm (11/4in.) 37.5 mm to 19.0 mm (11/2to 3/4in.) 16.0 mm (5/8in.) 19.0 mm to 9.5 mm (3/4to 3/8in.) 8.0 mm (5/16in.) 9.5 mm to 4.75 mm (3/8in. to No. 4) 4.0 mm (No. 5) 2014 by the American Association of State Highway and Transporta
49、tion Officials.All rights reserved. Duplication is a violation of applicable law.TS-1c T 103-6 AASHTO 8.1.2. Samples of fine aggregate shall be sieved over the original retaining sieve to determine their loss. The material retained on each sieve shall be weighed and the mass recorded. 8.1.3. In the case of ledge rock, the loss in mass shall be determined by subtracting from the original mass of the sa
