1、Designation: D6608 00 (Reapproved 2006)D6608 12Standard Practice forthe Identification of Trinidad Lake Asphalt in Asphalt Mixes1This standard is issued under the fixed designation D6608; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice shall be used for the qualitative determination of Trinidad Lake Asphalt in Trinidad La
3、ke Modified AsphaltCements obtained from production blends or recovered binder from asphalt paving mixtures.1.2 The values stated is SI units are to be regarded as standard. No other units of measurement are included in this standard1.3 It is limited to the binder content of Trinidad Lake Modified A
4、sphalt (Specification D5710) used in the construction ofasphalt pavements.1.4 WarningMercury has been designated by the United States Environmental Protection Agency and many state agenciesas a hazardous material that can cause central nervous system, kidney and liver damage. Mercury, or its vapor,
5、may be hazardousto health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See theapplicable Material Safety Data Sheet (MSDS) for details and EPAs websitehttp:/www.epa.gov/ mercury/index.htmforadditional information. Users should be aware th
6、at selling mercury and/or mercury containing products into your state may beprohibited by state law.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and heal
7、th practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D140 Practice for Sampling Bituminous MaterialsD1856 Test Method for Recovery of Asphalt From Solution by Abson MethodD2172 Test Methods for Quantitative Extraction of Bitume
8、n From Bituminous Paving MixturesD5710 Specification for Trinidad Lake Modified AsphaltE1 Specification for ASTM Liquid-in-Glass Thermometers3. Summary of Test Method3.1 A polished copper strip is immersed in a given quantity of sample and heated at a temperature and for a given timecharacteristic o
9、f the material being tested. At the end of this period the copper strip is removed, washed, and compared with theclassifications of the TLA Copper Tarnishing Ranges for copper strips.4. Significance and Use4.1 Bitumen contains sulfur compounds most of which are removed during refining, the resulting
10、 asphalt cement also containssulfur compounds which are released at the temperatures above 230C (446F) Trinidad Lake Modified Asphalt contains sulfurcompounds, which are released at lower temperatures between 170C (338F) and 230C (446F) The release of sulfur fromTrinidad Lake Modified Asphalt tarnis
11、hes the copper strip and appears to be related directly to the total TLA content. The copperstrip test is designed to assess the qualitative presence of TLA in asphalt cements.1 This practice is under the jurisdiction ofASTM Committee D04 on Road and Paving Materials and is the direct responsibility
12、 of Subcommittee D04.47 on MiscellaneousAsphalt Tests.Current edition approved June 1, 2006Dec. 1, 2012. Published June 2006December 2012. Originally approved in 2000. Last previous edition approved in 20002006 asD6608 00.D6608 00(2006). DOI: 10.1520/D6608-00R06.10.1520/D6608-12.2 For referencedASTM
13、 standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of
14、 an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as pub
15、lished by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Apparatus5.1 Test Tubes, 25 by 150 mm.5.2 Provide a bath, which can maintain a constant temperature of 210 6 1C (410 6 2F) and
16、 225 6 1C (437 6 2F). Thebath should have suitable supports to hold the test tubes in a vertical position and immersed to a depth of about 100-mm (4-in.).Oil or aluminum block baths are suitable.5.3 Thermometer, Thermometric Device, partial immersion thermometer for indicating the required test temp
17、erature, withgraduations 1C (2F) or less. The ASTM 2C (2F) thermometer is suitable. Any other thermometric device of equal accuracy maybe used.5.4 Polishing Vise, to hold the copper strip firmly without marring the edge while polishing. Any suitable holder may be usedprovided that the surface is hel
18、d tightly and the surface being polished is supported above the surface of the holder.5.5 Viewing Test Tubes, flat glass test tubes, are convenient for protecting corroded strip and may be used for close inspectionand storage.6. Materials6.1 Wash SolventAny volatile, sulfur free hydrocarbon solvent
19、may be used that would show no tarnish when tested at 210Cor 225C.NOTE 1Toluene is a suitable solvent.6.1 Polishing Materials:6.1.1 Silicone carbide grip paper of varying degrees of fineness including 65 m (240 grit) paper or cloth.6.1.2 Silicone carbide grains 105 m (150mesh).6.1.3 Absorbent cotton
20、 (cotton wool), pharmaceutical grade.6.2 Copper Strips:6.2.1 SpecificationsUse strips 12.5 mm (12 in.) wide, 1.5 to 3.0 mm (116 to 18 in.) thick, cut 75 mm (3 in.) long fromsmooth-surface, hard temper, cold-finished copper of 99.9+ % purity; electrical bus bar stock is generally suitable (see AnnexA
21、1).The strips may be used repeatedly but should be discarded when the surfaces become deformed on handling.6.2.2 Surface PreparationRemove all surface blemishes from all six sides of the strip with silicone carbide paper of suchvarying degrees of fineness as are needed to accomplish the desired resu
22、lts efficiently. Finish with 65m (240 grit) silicone carbidepaper or cloth, removing all marks that may have been made by other grades of paper used previously. Immerse the strip in washsolvent from which it can be withdrawn immediately for final preparation (polishing) or in which it can be stored
23、for future use.6.2.2.1 As a practical manual procedure for the surface preparation, place a sheet of paper on a flat surface, moisten it withkerosene or wash solvent, and rub the strip against the paper with a rotary motion, protecting the strip from contact with the fingersusing an ashless filter p
24、aper. Alternatively, the surface of the strip can be prepared by use of motor-driven machines usingappropriate grades of dry paper or cloth.6.2.3 Final PreparationRemove a strip from the wash solvent. Holding it in the fingers protected with ashless filter paper,polish first the ends and then the si
25、des with the 105m (150mesh) silicone carbide grains picked up from a clean glass plate witha pad of cotton (cotton wool) moistened with a drop of wash solvent. Wipe vigorously with fresh pads of cotton (cotton wool) andsubsequently handle only with stainless steel forceps. Do not touch with fingers.
26、 Clamp in a vise and polish the main surfaces withsilicone carbide grains on absorbent cotton. Do not polish in a circular motion. Rub in the direction of the long axis of the strip,carrying the stroke beyond the end of the strip before reversing direction. Clean all metal dust from the strip by rub
27、bing vigorouslywith clean pads of absorbent cotton until a fresh pad remains unsoiled. When the strip is clean, immediately immerse it in theprepared sample.6.2.3.1 It is important to polish the whole surface of the strip uniformly to obtain a uniformly stained strip. If the edges showwear (surface
28、elliptical) they will likely show more corrosion than the center. The use of a vise will facilitate uniform polishing.6.2.3.2 It is important to follow the order of preparation with the correctly sized silicone carbide material as described in6.3.26.2.2 and 6.3.36.2.3. The final preparation is with
29、105m silicone carbide grains. This is a larger grain size than the 65mpaper used in the surface preparation stage. The reason for this use of larger silicone carbide grains in the final preparation is toproduce asperities (controlled roughness) on the surface of the copper which acts as sites for th
30、e initiation of corrosion reactions.7. Reagent7.1 Wash SolventAny volatile, sulfur free hydrocarbon solvent may be used that would show no tarnish when tested at 210Cor 225C.NOTE 1Toluene is a suitable solvent.D6608 1228. Sample Preparation8.1 The binder shall be acquired either from production tank
31、s, according to Practice D140, or from asphalt mixes, accordingto the procedures inTest Method D2172 andTest Method D1856. Store the sample material in a clean, dark glass or metal containeror other suitable containers such that the properties of the sample are not affected. Fill the containers as c
32、ompletely as possibleand seal immediately.8.2 To produce a test sample, heat the recovered binder slowly to approximately 135C with constant stirring, by hand, untilmolten. Stir the sample thoroughly again before decanting into the sample test tubes.9. Procedure9.1 Place 1520 mL of the molten recove
33、red binder sample, which is free of any entrained water or suspended water, into eachof two clean and dry test tubes. Insert a polished copper strip into each test tube within one (1) minute of completing the final strippreparation. Ensure that the strip is vertically held in the sample with approxi
34、mately 4457 mm (134 214 in.) of the stripprojecting out of the sample mixture.9.2 Place the test tubes in the bath, which has been maintained at 210C and leave for 25 min.9.3 Strip Examination:9.3.1 Empty the contents of each test tube into a 150mL tall-form beaker, allowing the strip to slide out g
35、ently to avoidbreakage. Remove the strip immediately with clean stainless steel forceps and immerse in the wash solvent for not longer than 30s. Remove and blot dry with quantitative filter paper. Inspect the strip for evidence of tarnishing or color change while holdingat an angle of approximately
36、45. Compare the strip to the classification given in the TLA Copper Tarnishing Ranges (see Table1).9.3.2 In handling the test strip during inspection, care must be taken to avoid damage by marking or staining. A flat glass tube,which can be stoppered with absorbent cotton, may be used as a viewing a
37、id.9.4 If the surface of the strip is unchanged, raise the bath temperature to 225C and allow to stand for 25 min. Replace the stripin the test tube and place in the bath for 25 min. Repeat paragraph 8.39.3 for strip examination.10. Interpretation10.1 Interpret the Trinidad Lake Asphalt presence and
38、 content of the sample accordingly as the appearance of the test stripagrees with one of the strips in the TLA Copper Tarnishing Standard in Table 1.10.2 If there is a color change at 210C, conclude that the bitumen contains TLA and has a TLA content greater than 25 %.10.3 If there is a color change
39、 at 225C, conclude that the binder contains TLA and has a TLA content of less than 25 %.11. Report11.1 Report the results as the presence of greater than 25 % of TLA, the presence of less than 25 % of TLA or the absence ofTLA in the asphalt mix.12. Keywords12.1 asphalt mix; copper strip finish; copp
40、er tarnishing; sulfur compound; Trinidad Lake AsphaltANNEXA1. COPPER QUALITYTABLE 1 TLA Copper Tarnishing RangesClassification Temperature,C Designation Description TLAPresence1 210 None Clean Strip 0 25 %TLAA2 210Moderate toheavytarnishDark blue,black-green 25 % TLA3 225Slight tomoderatetarnishRed-
41、blue,green 25 % TLA4 225 None Clean strip 0 % TLAA Further testing at 225C is required for determination of the absence or presenceof TLA.D6608 123A1.1 Copper QualityA1.1.1 Hard-tempered, cold-finished type (ETP) electrolytic tough pitch copper. 33 Conforming to Copper Development Assn. (CDA), Unite
42、d States of America No. 110, or to British Standard (BS) 1036:1952, which have proper quality.D6608 124ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that d
43、etermination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved
44、 or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel t
45、hat your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprint
46、s (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D6608 125
