1、Standard Method of Test for Plastic Fines in Graded Aggregates and Soils by Use of the Sand Equivalent Test AASHTO Designation: T 176-08 (2013) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1a T 176-1 AASHTO Stan
2、dard Method of Test for Plastic Fines in Graded Aggregates and Soils by Use of the Sand Equivalent Test AASHTO Designation: T 176-08 (2013) 1. SCOPE 1.1. This test is intended to serve as a rapid test to show the relative proportions of fine dust or claylike material in soils or graded aggregates. 1
3、.2. The following applies to all specified limits in this standard: For the purpose of determining conformance with these specifications, an observed value 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,
4、in accordance with E 29, Using Significant Digits in Test Data to Determine Conformance with Specifications. 1.3. The values stated in SI units are to be regarded as the standard. 1.4. This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address
5、 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 use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 92, Wire-Cloth Siev
6、es for Testing Purposes M 231, Weighing Devices Used in the Testing of Materials T 2, Sampling of Aggregates T 248, Reducing Samples of Aggregate to Testing Size 2.2. ASTM Standard: E 29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications 3. SIGN
7、IFICANCE AND USE 3.1. This test method is used to determine the proportion of detrimental fines in the portion passing the 4.75-mm (No. 4) sieve of soils or graded aggregates. 4. APPARATUS 4.1. Sand Equivalent ApparatusA graduated plastic cylinder, rubber stopper, irrigator tube, weighted foot assem
8、bly, and siphon assembly, all conforming to their respective specifications and 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a T 176-2 AASHTO dimensions shown in Figure 1. Fit the siphon assembly
9、to a 4-L (1-gal) bottle of working calcium chloride solution (see Section 2.8) placed on a shelf 915 25 mm (36 1 in.) above the work surface. In lieu of the specified 4-L (1-gal) bottle, a glass or plastic vat having a larger capacity may be used provided the liquid level of the working solution is
10、maintained between 915 and 1170 mm (36 and 46 in.) above the work surface. (See Figure 2.) Assembly No. Reg. Description Stock Size Material Heat Treatment A Siphon Assembly 1 Siphon tube 6.4 dia 400 Copper tube 2 Siphon hose 4.8 ID 1220 Rubber tube 3 Blow hose 4.8 ID 50.8 Rubber tube 4 Blow tube 6.
11、4 dia 50.8 Copper tube 5 Two-hole stopper No. 6 Rubber 6 Irrigator tube 6.4 OD 0.89 wall 500 stainless tube, type 316 7 Clamp Pinchcock, Day, BKH No. 21730 or equivalent B Graduate Assembly 8 Tube 38.1 OD 430 Trans acrylic plastic 9 Base 12.7 102 102 Trans acrylic plastic C Weighted Foot Assembly 10
12、 Sand reading indicator 6.4 dia 14.9 Nylon 101 Type 66 Annealed 11 Rod 6.4 dia 438.2 Brass 12 Weight 50.8 dia 52.78 Cold rolled steel, or equivalent 13 Roll pin 0.16 dia 12.7 Steel 14 Foot 0.16 Hex 13.7 Brass 15 Solid stopper No. 7 Rubber Notes: 1. “C” Weighted Foot Assembly to Weigh 1000 5g. 2. Gra
13、duations on graduate to be 2.54 mm apart and every tenth mark to be numerically designated as shown. Every fifth line should be approximately 9.5 mm long. All other lines should be approximately 5.5 mm long. Depth is to be 0.4 mm. Width is to be 0.8 mm across the top. 3. Accuracy of scale to be 0.25
14、 mm per 2.5 mm. Error at any point on scale to be 0.75 mm of true distance to zero. 4. Glass or stainless steel may be substituted as a material type for the copper siphon and blow tubing. Figure 1Sand Equivalent Apparatus (continued on the following two pages) 2014 by the American Association of St
15、ate Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.102mm102mm25-mmDia.Wooddowel75mmlong.Drillaxiallytofitirrigatortube.Splitdowellongitudinally.GluetoupperendofirrigatortubeorwrapwithtapefortightOptionalHandleforIrrigatorTubeASSEMBLY AWeight12A
16、SSEMBLY B32mm1.660.8Dia52.78approx.543approx.250mmtofitaverage4-LjugSeeNote 1orotherworkingsolutionreservoirSeedetail167231.5 0.512.7381.0 0.7mm430mm892viewsasshownFlareapprox.frictionfit.Detail6Completelycloseendandsolderifnecessary.pinchasshown.SilverAnnealendonlyandleavenosharpedges.90 0.5Mch.end
17、ofCyl.flatforperfectbondtobasewithEthylenedichlorideorsuitablesolventSeeNotes2and 3Bevelapprox.asshownforgoodW/15stopper38.1Drill15.7Dia x7.8deep90apart510mm3.2Drill#60throughIrrigatorTube6Detail#60drill2placesBendtosuitDrillandtapfor14in.28THDand34in.deepSeeDetail 6Note: All dimensionsareshown in m
18、illimetersunlessotherwiseindicated.Figure1SandEquivalentApparatus(continued)TS-1a T 176-3 AASHTO 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.SandReadingIndicator10Rod11ASSEMBLY C14Foot25.4mm13.72.5Dr
19、illandtapfor14-in.28THDx38in.deep60turnO.D.to30.212.7Dia28.7Dia.1.6mm6.4mm15mm3.3mm6.35 0.025holefor arollpin(oneside)Drill116-in.guidehole306.3mm19mm14-in.28THDbothends256.5116-in.drillthroughrodandindicator.AttachwithItem13Rollpin.Screwfoottightonbasebeforemeasuringanddrilling.UseLocktiteorequival
20、entforpermanentset.1410111215440mmNote: All dimensionsareshown inmillimetersunlessotherwiseindicated.Figure1SandEquivalentApparatus(continued)TS-1a T 176-4 AASHTO 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applica
21、ble law.TS-1a T 176-5 AASHTO Figure 2Graduated Cylinder, Irrigator Tube, Weighted Foot Assembly, and Siphon Note 1An older model of a weighted foot assembly has a guide cap that fits over the upper end of the graduated cylinder and centers the rod in the cylinder; the foot of the assembly has a coni
22、cal upper surface and three centering screws to center it loosely in the cylinder. The older model does not have the sand reading indicator affixed to the rod (Figure 1), but a slot in the centering screws of the weighted foot is used to indicate the sand reading. Apparatus with the sand reading ind
23、icator (Figure 1) is preferred for testing clayey materials. 4.2. MeasureA tinned measure, having a capacity of 85 5 mL (3 oz), approximately 57 mm (2.25 in.) in diameter. 4.3. BalanceThe balance shall have sufficient capacity, be readable to not more than 0.1 percent of the sample mass, and conform
24、 to the requirements of M 231. 4.4. FunnelA wide-mouth funnel approximately 100 mm (4 in.) in diameter at the mouth. 4.5. TimerA clock or watch reading in minutes and seconds. 4.6. Mechanical ShakerA mechanical shaker having a throw of 203.2 1.0 mm (8.00 0.04 in.) and operating at 175 2 cpm (2.92 0.
25、03 Hz) (Note 2). Prior to use, fasten the mechanical sand equivalent shaker securely to a firm and level mount. 4.7. Manual ShakerA manually operated shaker, capable of producing an oscillating motion at the rate of 100 complete cycles in 45 5 s, with a hand-assisted half stroke length of 127 5 mm (
26、5.0 0.2 in.). The shaker shall be fastened securely to a firm and level mount by bolts or clamps if a large number of determinations are to be made. 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a
27、T 176-6 AASHTO Note 2The mechanical shaker shall be used when performing reference sand equivalent determinations. Either the mechanical or manually operated shaker should be used in lieu of the hand method whenever possible. 4.8. Stock SolutionThe materials listed in Sections 4.8.1, 4.8.2, or 4.8.3
28、 may be used to prepare the stock solution. A fourth alternative is not to use any biocide, provided the time of storage of stock solution is not sufficient to promote the growth of fungi. 4.8.1. Stock solution with formaldehyde. 4.8.1.1. Anhydrous calcium chloride, 454 g (1.0 lb) of technical grade
29、. 4.8.1.2. USP glycerin, 2050 g (4.515 lb). 4.8.1.3. Formaldehyde, (40 volume percent solution) 47 g (0.10 lb). 4.8.1.4. Dissolve the 454 g (1.0 lb) of calcium chloride in 1.89 L (1/2gal) of distilled water. Cool and filter it through ready pleated rapid filtering paper. Add the 2050 g (4.515 lb) of
30、 glycerin and the 47 g (0.10 lb) of formaldehyde to the filtered solution, mix well, and dilute to 3.78 L (1 gal). 4.8.2. Stock solution with glutaraldehyde. 4.8.2.1. Calcium chloride dihydrate, 577 g (1.27 lb) of A.C.S. grade. Note 3A.C.S.-grade calcium chloride dihydrate is specified for the stock
31、 solution prepared with glutaraldehyde because tests indicate that impurities in the technical grade anhydrous calcium chloride may react with the glutaraldehyde resulting in an unknown precipitate. 4.8.2.2. USP glycerin, 2050 g (4.515 lb). 4.8.2.3. 1.5-pentanedial (glutaraldehyde), 50 percent solut
32、ion in water 59 g (0.13 lb). 4.8.2.4. Dissolve the 577 g (1.27 lb) of calcium chloride dihydrate in 1.89 L (1/2gal) of distilled water. Cool and add the 2050 g (4.515 lb) of glycerin and the 59 g (0.13 lb) of glutaraldehyde to the solution, mix well, and dilute to 3.78 L (1 gal). Note 41.5-pentanedi
33、al, also known as glutaraldehyde, glutaric dialdehyde, and trade name UCARCIDE 250, may be obtained as glutaraldehyde solution 50 percent.14.8.3. Stock solution with Kathon CG/ICP. 4.8.3.1. Calcium chloride dihydrate, 577 g (1.27 lb) of A.C.S. Grade. 4.8.3.2. USP glycerin, 2050 g (4.515 lb). 4.8.3.3
34、. Kathon CG/ICP, 63 g (0.14 lb). 4.8.3.4. Dissolve the 577 g (1.27 lb) of calcium chloride dihydrate in 1.89 L (1/2gal) of distilled water. Cool and add the 2050 g (4.515 lb) of glycerin and the 63 g (0.14 lb) of Kathon CG/ICP to the solution, mix well, and dilute to 3.78 L (1 gal).24.9. Working Sol
35、utionWorking calcium chloride solution: Prepare the working calcium chloride by diluting one measuring tin full (85 5 mL) of the stock calcium chloride solution to 3.8 L (1 gal) with water. Use distilled or demineralized water for the normal preparation of the working solution. However, if it is det
36、ermined that the local tap water is of such purity that it does not affect the test results, it is permissible to use in lieu of distilled or demineralized water except in the event of dispute. Working solutions more than 30 days old shall be discarded. 2014 by the American Association of State High
37、way and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1a T 176-7 AASHTO 4.10. StraightedgeA straightedge or spatula, suitable for striking off the excess soil from the tin measure. 4.11. OvenA thermostatically controlled drying oven capable of maintain
38、ing a temperature of 110 5C (230 9F). 4.12. Quartering ClothQuartering or splitting cloth, approximately 600 mm (2 ft) square, nonabsorbent material such as plastic or oil cloth. 4.13. SieveA 4.75-mm (No. 4) sieve conforming to the requirements of M 92. 4.14. Optional Handle for Irrigation TubeA 25-
39、mm diameter wooden dowel to aid in pushing the irrigation tube into firm materials. See Figure 1, Assembly B. 5. TEMPERATURE CONTROL 5.1. The temperature of the working solution should be maintained at 22 3C (72 5F) during the performance of this test. If field conditions preclude the maintenance of
40、 the temperature range, frequent reference samples should be submitted to a laboratory where proper temperature control is possible. It is also possible to establish temperature correction curves for each material being tested where proper temperature control is not possible. However, no general cor
41、rection curve should be utilized for several materials even within a narrow range of sand equivalent values. Samples that meet the minimums and equivalent requirement at a working solution temperature below the recommended range need not be subject to reference testing. 6. SAMPLING 6.1. Obtain a sam
42、ple of the material to be tested in accordance with T 2. 6.2. Reduce the sample according to T 248. The sample shall be of sufficient size to yield 1000 to 1500 g of material passing the 4.75-mm (No. 4) sieve. 6.3. Sieve the sample over a 4.75-mm (No. 4) sieve. All aggregations of fine-grained soil
43、material shall be pulverized to pass the 4.75-mm (No. 4) sieve, and all fines shall be cleaned from the particles retained on the 4.75-mm (No. 4) sieve and included with the material passing the 4.75-mm (No. 4) sieve. 6.4. Split or quarter the material passing the 4.75-mm (No. 4) sieve to yield 500
44、to 750 g (1.1 to 1.6 lb) of material. Use extreme care to obtain a truly representative portion of the original sample (Note 5). Note 5Experiments show that as the amount of material being reduced by splitting or quartering is decreased, the accuracy of providing representative portions is reduced.
45、It is imperative that the sample be split or quartered carefully. When it appears necessary, dampen the material before splitting or quartering, to avoid segregation or loss of fines. 2014 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a
46、 violation of applicable law.TS-1a T 176-8 AASHTO 7. SAMPLE PREPARATION 7.1. Prepare the desired number of test samples by one of the following methods: 7.1.1. Alternate Method No. 1Air Dry. 7.1.1.1. Split or quarter enough material from the portion passing the 4.75-mm (No. 4) sieve to fill the 85-m
47、L (3-oz) tin measure so it is slightly rounded above the brim. While filling the measure, tap the bottom edge of the tin on the work table or other hard surface to cause consolidation of the material and allow the maximum amount to be placed in the tin. Strike off the tin with the spatula or straigh
48、tedge so the material is level with the top of the measuring tin. 7.1.2. Alternate Method No. 2Pre-Wet. 7.1.2.1. The sample must be in the proper moisture condition to achieve reliable results. This condition is determined by tightly squeezing a small portion of the thoroughly mixed sample in the pa
49、lm of the hand. If the cast that is formed permits careful handling without breaking, the correct moisture range has been obtained. If the material is too dry, the cast will crumble and it will be necessary to add water, remix, and retest until the material forms a cast. If the material shows any free water it is too wet to test and must be drained and air dried, mixing it frequently to ensure uniformity. This overly wet material will form a good cast when checked initiall
