1、Designation: D6924 03 (Reapproved 2017)Standard Specification forPreformed Thermoplastic Vulcanizate Elastomeric JointSeals for Bridges1This standard is issued under the fixed designation D6924; the number immediately following the designation indicates the year oforiginal adoption or, in the case o
2、f revision, 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 specification covers the material requirements forpreformed thermoplastic vulcanizate (TP
3、V) elastomeric jointseals for bridges. The seal consists of a multiple-web designcomposed of a TPV and functions only by compression of theseal between the faces of the joint with the seal folding inwardat the top to facilitate compression. The seal is installed with alubricant adhesive and is desig
4、ned to seal the joint and rejectincompressibles.NOTE 1This specification may not be applicable for seals whoseheight is less than 90 % of its nominal width.1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are providedfor information only.1.
5、3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements prior to use.1.4 This interna
6、tional standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Com
7、mittee.2. Referenced Documents2.1 ASTM Standards:2D395 Test Methods for Rubber PropertyCompression SetD412 Test Methods for Vulcanized Rubber and Thermoplas-tic ElastomersTensionD518 Test Method for Rubber DeteriorationSurfaceCracking (Withdrawn 2007)3D573 Test Method for RubberDeterioration in an A
8、irOvenD575 Test Methods for Rubber Properties in CompressionD1149 Test Methods for Rubber DeteriorationCracking inan Ozone Controlled EnvironmentD2240 Test Method for Rubber PropertyDurometer Hard-nessD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black Man
9、ufacturingIndustriesD6338 Classification System for Highly Crosslinked Ther-moplastic Vulcanizates (HCTPVs) Based on ASTM Stan-dard Test Methods3. Marking and Ordering Information3.1 Each lot of seal shall be marked with characters of notless than 0.25 in. (6.35 mm) in height on the top of the seal
10、ata maximum of 4-ft (1.22-m) intervals showing the lot number,date of manufacture, and the manufacturing seal designation.3.2 The purchaser shall specify the anticipated requiredminimum acceptable joint movement, and either the minimumjoint opening, or the nominal width of seal.4. Materials and Manu
11、facture4.1 The seals shall be preformed, and the material shall bevulcanized elastomeric compound using a thermoplastic vul-canizate as the compound. A thermoplastic vulcanizate is ablend of a crosslinked rubber and a thermoplastic polymer thatcan be processed on conventional thermoplastic processin
12、gmachinery and has the properties of a crosslinked elastomer.Highly crosslinked thermoplastic elastomers are classifiedaccording to Classification System D6338. TPV materials aremade in the dynamic vulcanization process. One example of atypical TPV is crosslinked ethylene propylene diene rubberblend
13、ed with polypropylene. The TPV material can alsocontain processing oils, antioxidants, fillers, or other additives.1This specification is under the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.34 onPreformed Joint Fillers, Sealer
14、s and Sealing Systems.Current edition approved July 1, 2017. Published July 2017. Originally approvedin 2003. Last previous edition approved in 2012 as D6924 03 (2012). DOI:10.1520/D6924-03R17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at se
15、rviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,
16、 PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organizatio
17、n Technical Barriers to Trade (TBT) Committee.15. Physical Requirements5.1 The materials shall conform to the physical propertiesprescribed in Table 1.5.2 In the applicable requirements of Table 1 and the testmethods, all deflection shall be based on the nominal width.6. Dimensions and Working Param
18、eters6.1 The size, shape, and dimensional tolerances shall be asoutlined in 6.1.1.6.1.1 Measurements used for laboratory testing shall betaken to the nearest 0.01 in. (0.3 mm) and reported/recorded tothe nearest 0.1 in. (3 mm) as the average of three measure-ments. The measured width shall be greate
19、r than or equal to thenominal width. The seal height shall not be less than 90 % ofthe nominal width unless joint recess dimensions or specialdesign considerations dictate the geometry.6.2 Compression Deflection PropertiesThe contact pres-sure expressed in pounds-force per square inch (or pascals)wh
20、en the seal is compressed to any particular width indicatesthe stress-strain relationship that exists in the seal. Thisrelationship is dependent on both the properties of the elasto-mer and the cross-sectional configuration of the seal.Therefore, for a predetermined allowable pressure, a definitiver
21、elationship will exist and the working limits of the seal may bedefined.6.2.1 The working limits (minimum and maximum degreesof compression) of the seal shall be determined on the basis ofthe minimum and maximum limits of compressibility (LCminand LCmax), and the movement range as specified herein.
22、Sealswith nominal width differing from that specified areacceptable, providing the compressed width at LCmaxis lessthan the minimum anticipated joint opening, and the movementrange requirement is met.6.2.2 The minimum limit of compressibility (LCmin)isdefined as the compressed width (expressed in te
23、rms of percentof nominal width) corresponding to a contact pressure of 3 psi(20.68 kPa). The LCminshall be determined in accordance with9.3. For the purpose of calculating movement range, a value at85 % of nominal width shall be used for LCminwhen themeasured value of LCminexceeds 85 %.NOTE 2If the
24、seal generates a pressure of 3 psi at 90 % of nominalwidth, LCminequals 85 %. However, if the seal generates 3 psi at 70 % ofnominal width, the LCminequals 70 %.6.2.3 The maximum limit of compressibility (LCmax)isdefined as the compressed width (expressed in terms of percentof nominal width) corresp
25、onding to a contact pressure of 35 psi(241.32 kPa). The LCmaxshall be determined in accordancewith 9.3.LCmaxhas been designated at 35 psi (241.32 kPa) inorder to mitigate the tendencies toward pressure decay of theseal during use. A reading of 35 psi is considered an absolutemaximum pressure which s
26、hould not be exceeded.6.2.4 The movement range of the seal is defined as thenumerical difference between the LCminand the LCmaxex-pressed in inches (mm). For the purpose of calculating themovement range, a value at 85 % shall be used for LCminwhenthe measured value of LCminexceeds 85 %. For purposes
27、 ofacceptance testing, the calculated movement range of the sealshall not be less than the specified value.7. Sampling7.1 A lot shall consist of the quantity for each cross sectionagreed upon between the purchaser and the supplier.7.2 Samples shall be taken at random from each shipment ofmaterial. I
28、f the shipment consists of more than one lot, each lotshall be sampled.7.3 The minimum lengths of samples for testing purposesshall be as prescribed by the purchaser or as prescribed in Table2.8. Specimen Preparation8.1 All test specimens shall be cut, buffed, or both from thesample of preformed sea
29、l. Care should be taken not to overheatTABLE 1 Physical Requirements for Preformed ElastomericJoint SealsRequirementsASTMTest MethodTensile strength, min, psi (MPa) 730 (4.4) D412Elongation at break, min, % 300 D412Hardness, Type A durometer, points 50 to 70 D2240(modified)AOven aging, 168 h at 212
30、F(100 C)Tensile strength, max, % loss 10Elongation, max, % loss 10Hardness, Type A durometer,points change0to5Ozone resistanceBno cracks D1149C20 % strain, 300 pphm in air, 70 h,at 104 F (40 C) (wiped with tolueneto remove surface contamination)Low-temperature recovery,72 h at 14 F (10 C), 50 %:Defl
31、ection, min, % 80 Section 7DLow-temperature recovery,22 h at 20 F (29 C), 50 %:Deflection, min, % 70 Section 7DHigh-temperature recovery,70 h, at 212 F (100 C), 50 %:Deflection, min, % 75 Section 7DCompression-deflection properties:LCminin. (mm) 9.3 D575 Method ALCmaxin. (mm) 9.3 (modified)EMovement
32、 range, in. (mm) 9.3AThe term “modified” in the table relates to the specimen preparation. The use ofthe joint seal as the specimen source requires that more plies than specified ineither of the modified test procedures be used. Such specimen modification shallbe agreed upon between the purchaser an
33、d the supplier prior to testing. Thehardness test shall be made with the durometer in a durometer stand asrecommended in Test Method D2240.BSample prepared in accordance with Method A of Test Method D518.CCracking, splitting, or sticking of a specimen during a recovery test shall meanthat the specim
34、en has failed the test.DThe reference section and subsections are those of this specification. The valuesfound in 6.2.2, 6.2.3, and 6.2.4 shall be within the range specified by the purchaserin 3.2.ESpeed of testing shall be 0.5 0.05 in. (13 1.3 mm), min at room temperatureof 73 4 F (23 2.2 C). The s
35、heets of sandpaper are not used.TABLE 2 Minimum Lengths of Seal SamplesSeal Size,in. (mm)Length of Sample,in. (m)Less than 2 (51) 96 (2.44)2 (51) to less than 3 (76) 72 (1.83)3 (76) and larger 60 (1.52)D6924 03 (2017)2the test specimen during buffing. The cut shall be square towithin 2 and smooth, w
36、ith no roughness visible to the nakedeye. The use of a tooth blade device or a guillotine-type cutter,or both, is not acceptable. This process will eliminate irregu-larities.8.2 Specimens for determining tensile strength and elonga-tion (Test Methods D412) shall be prepared using Die C whenpossible.
37、 Die D may be used when the flat sections of a seal aretoo small for Die C. However, the requirement of Table 1 shallapply regardless of the die used. Buffing should be carefullyperformed and kept to a minimum.8.3 Specimens for low-temperature and high-temperaturerecovery tests and for pressure defl
38、ection tests shall consist of6-in. (150-mm) lengths of the preformed seal.9. Test Methods9.1 Compliance with the requirements of Table 1 shall bedetermined by tests conducted in accordance with the methodsspecified.9.2 Recovery Tests:9.2.1 Determine the low-temperature and high-temperaturerecovery t
39、est values using specimens prepared in accordancewith Section 8. Two specimens shall be used for each test.9.2.2 Deflect the specimen between parallel plates to 50 %of the nominal width using the compression set clamp assem-bly described in Method B of Test Methods D395. Prior tocompression, place t
40、he specimen in a horizontal position, suchthat the plane through both edges of the top surface of the jointseal is perpendicular to the compression plate.As the specimenis being compressed, the top surface of the joint seal shouldfold inward toward the center of the specimen.9.2.3 Place a clamp asse
41、mbly containing the compressedspecimen in a refrigerated box capable of maintaining atemperature of 14 6 2 F (10 6 1.1 C) for 72 h. Unclamp theassembly and remove the upper compression plate, or carefullyremove the specimen from the assembly and transfer it to awooden surface in the refrigerated box
42、. Allow the specimen torecover for1hat146 2 F (10 6 1.1 C). Measure therecovered width in the center of the 6-in. (150-mm) length atthe top longitudinal edge of the specimen. Measurements maybe made with either a dial caliper or a platform-mounted dialgage graduated in thousandths of an inch (0.025
43、mm). Theplatform-mounted gage shall have a14-in. (6-mm) diameterpressure foot with a force of 0.18 6 0.02 lbf (0.80 6 0.09 N).Measurements with the platform-mounted gage should betaken with the pressure foot centered on the longitudinal edgeof the seal. Calculate the recovery as follows:Recovery, %
44、5recovered width 3100!nominal width!(1)Report the least value of recovery to the nearest 1 %.NOTE 3The use of a desiccant, such as calcium chloride, in therefrigerated box should be used to minimize frosting. The desiccant shouldbe changed or reactivated as frequently as necessary to keep it effecti
45、ve.9.2.4 Place a clamp assembly containing the compressedspecimen in a refrigerated box capable of maintaining atemperature of 20 6 2 F (29 6 1.1 C) for 22 h (see Note3). Unclamp the assembly and remove the upper compressionplate, or carefully remove the specimen and transfer it to awooden surface i
46、n the refrigerated box. Allow the specimen torecover for1hat206 2 F (29 6 1.1 C). Measure therecovered width and calculate the recovery as in 9.2.3.9.2.5 Place a clamp assembly containing the compressedspecimen in an oven conforming to Test Method D573. Thetemperature shall be maintained at 212 6 2
47、F (100 6 1.1 C)for 70 h. Do not preheat the clamp assembly. Unclamp theassembly, carefully remove the specimen, and allow it torecover at 73 6 4 F (23 6 2.2 C) on a wooden surface for1 h. Measure the recovered width and calculate the recovery asin 9.2.3.9.3 Compression Deflection Tests:9.3.1 Determi
48、ne compression deflection values using speci-mens prepared in accordance with Section 8. Measure thelength of each specimen at the top, center, and bottom using arule graduated in thirty-seconds of an inch (or millimetres).Average the three measurements and record as the length of thespecimen to the
49、 nearest132 in. (0.8 mm). Measure the height ofthe contact area on both sides and at both ends (four measure-ments) with a dial caliper or suitable rule. Average and recordto the nearest132 in. (0.8 mm).9.3.2 Calculate the contact area of the specimen by multi-plying the average length times the average height of thecontact area as determined above.9.3.3 Calculate the forces required to compress the speci-men to LCminand LCmaxby multiplying the contact area times3 psi (20.68 kPa) and 35 psi (241.32 kPa), respectively
