1、Designation: D 3542 92 (Reapproved 2003)Standard Specification forPreformed Polychloroprene Elastomeric Joint Seals forBridges1This standard is issued under the fixed designation D 3542; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the material requirements forpreformed polychloroprene elastomeric joint se
3、als for bridges.The seal consists of a multiple-web design composed ofpolychloroprene and functions only by compression of the sealbetween the faces of the joint with the seal folding inward atthe top to facilitate compression. The seal is installed with alubricant adhesive and is designed to seal t
4、he joint and rejectincompressibles.NOTE 1This specification may not be applicable for seals whoseheight is less than 90 % of its nominal width.1.2 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 standar
5、d to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.3 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are providedfor information only.2. Referenced Documents2.1 AST
6、M Standards:2D 412 Test Methods for Vulcanized Rubber and Thermo-plastic ElastomersTensionD 471 Test Method for Rubber PropertyEffect of LiquidsD 518 Test Method for Rubber DeteriorationSurfaceCrackingD 573 Test Method for RubberDeterioration in an AirOvenD 575 Test Methods for Rubber Properties in
7、CompressionD 1149 Test Method for Rubber DeteriorationSurfaceOzone Cracking in a ChamberD 2240 Test Method for Rubber PropertyDurometerHardnessD 3183 Practice for RubberPreparation of Pieces for TestPurposes from Products3. Marking and Ordering Information3.1 Each lot of seal shall be marked with ch
8、aracters of notless than 0.25 in. (6.35 mm) in height on the top of the seal ata maximum of 4 ft (1.22 m) intervals showing the lot number,date of manufacture, and the manufacturing seal designation.The seal shall also have die markings which are registered withthe Rubber Manufacturers Association (
9、RMA).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 Manufacture4.1 The seals shall be preformed, and the material shall bevulcanized elastomeric compound using virgin polych
10、loro-prene as the only polymer.5. 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 Parameters6.1 The siz
11、e, 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 greater than or equal t
12、o 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)1This specification
13、 is under the jurisdiction of ASTM Committee D04 on Roadand Paving Materials and is the direct responsibility of Subcommittee D04.34 onPreformed Joint Fillers, Sealers, and Sealing Systems.Current edition approved Nov. 15, 1992. Published January 1993. Originallyapproved in 1976. Last previous editi
14、on approved in 1998 as D 3542 92 (1998).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM Inter
15、national, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.when 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 elas-tomer and the cross-sect
16、ional configuration of the seal. There-fore, for a predetermined allowable pressure, a definitiverelationship 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 an
17、d maximum limits of compressibility (LC minand LC max), and the movement range as specified herein.Seals with nominal width differing from that specified areacceptable, providing the compressed width at LC max is lessthan the minimum anticipated joint opening, and the movementrange requirement is me
18、t.6.2.2 The minimum limit of compressibility (LC min) isdefined as the compressed width (expressed in terms of percentof nominal width) corresponding to a contact pressure of 3 psi(20.68 kPa). The LC min shall be determined in accordancewith 9.3. For the purpose of calculating movement range, avalue
19、 at 85 % of nominal width shall be used for LC min whenthe measured value of LC min exceeds 85 %.NOTE 2If the seal generates a pressure of 3 psi at 90 % of nominalwidth, LC min equals 85 %. However, if the seal generates 3 psi at 70 %of nominal width, the LC min equals 70 %.6.2.3 The maximum limit o
20、f compressibility (LC max) isdefined as the compressed width (expressed in terms of percentof nominal width) corresponding to a contact pressure of 35 psi(241.32 kPa). The LC max shall be determined in accordancewith 9.3. LC max has been designated at 35 psi (241.32 kPa)in order to mitigate the tend
21、encies toward pressure decay of theseal during use. A reading of 35 psi is considered an absolutemaximum pressure which should not be exceeded.6.2.4 The movement range of the seal is defined as thenumerical difference between the LC min and the LC maxexpressed in inches (mm). For the purpose of calc
22、ulating themovement range, a value at 85 % shall be used for LC minwhen the measured value of LC min exceeds 85 %. Forpurposes of acceptance testing, the calculated movement rangeof the seal shall not be less than the specified value.7. Sampling7.1 A lot shall consist of the quantity for each cross
23、sectionagreed upon between the purchaser and the supplier.7.2 Samples shall be taken at random from each shipment ofmaterial. If 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 p
24、rescribed in Table2.TABLE 1 Physical Requirements for Preformed Elastomeric Joint SealsRequirements ASTM Test MethodTensile strength, min, psi (MPa) 2000 (13.8) D 412Elongation at break, min, % 250 D 412Hardness, Type A durometer, points 55 6 5 D 2240 (modified)AOven aging, 70 h at 212F (100C)Tensil
25、e strength, max, % loss 20Elongation, max,% loss 20Hardness, Type A durometer, points change 0 to 10Oil swell, ASTM Oil No. 3, 70 h at 212F:70 h at 212F (100C)Weight change, max, % 45 D 471Ozone resistanceBno cracks D 1149C20 % strain, 300 pphm in air, 70 h, at 104F (40C) (wiped with toluene to remo
26、ve surfacecontamination)Low-temperature recovery,72 h at 14F (14C), 50 %:Deflection, min, % 88 Section 7DLow-temperature recovery,22 h at 20F (29C), 50 %:Deflection, min, % 83 Section 7DHigh-temperature recovery,70 h, at 212F (100C), 50 %:Deflection, min, % 85 Section 7DCompression-deflection proper
27、ties:LC min in. (mm) See 8.3.5 D 575 Method A (modified)ELC max in. (mm) See 8.3.5Movement range, in. (mm) See 8.3.5AThe term “modified” in the table relates to the specimen preparation. The use of the joint seal as the specimen source requires that more plies than specified in eitherof the modified
28、 test procedures be used. Such specimen modification shall be agreed upon between the purchaser and the supplier prior to testing. The hardness test shallbe made with the durometer in a durometer stand as recommended in Test Method D 2240.BSample prepared in accordance with Method A of Test Method D
29、 518.CCracking, splitting, or sticking of a specimen during a recovery test shall mean that the specimen has failed the test.DThe reference section and subsections are those of this specification. The values found in 6.2.2, 6.2.3, and 6.2.4 shall be within the range specified by the purchaserin 3.2.
30、ESpeed of testing shall be 0.5 6 0.05 in. (13 6 1.3 mm), min at room temperature of 73 6 4F (23 6 2.2C). The sheets 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 l
31、arger 60 (1.52)D 3542 92 (2003)28. Specimen Preparation8.1 All test specimens shall be cut, buffed, or both from thesample of preformed seal. Care should be taken not to overheatthe test specimen during buffing. The cut shall be square towithin 2 and smooth, with no roughness visible to the nakedeye
32、. 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 Method D 412) shall be prepared using Die C whenpossible. Die D may be used when the flat section
33、s 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 deflection tests shall consist of6-in. (150-
34、mm) lengths of the preformed seal. Low-temperature recovery and pressure deflection specimens shallbe lightly dusted with talc on all internal and external surfaces.Specimens for high-temperature recovery shall be lightlydusted with talc on the external surfaces only.9. Test Methods9.1 Compliance wi
35、th 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 test values using specimens prepared in accordancewith Section 8. Two specimens shall be used for each test
36、.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 Method D 395. Prior tocompression, place the specimen in a horizontal position, suchthat the plane through both edges of the top surface of the join
37、tseal 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 assembly containing the compressedspecimen in a refrigerated box capable of maintaining atemperature of 146 2
38、F (10 6 1.1C) 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. Allow the specimen torecover for1hat146 2F (10 6 1.1C). Measure therecovered width in the center of the 6-
39、in. (150mm) 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 mm). Theplatform-mounted gage shall have a14-in. (6mm) diameterpressure foot with a force of 0.18 6 0.02 lbf (0
40、.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, % 5recovered width 3 100!/nominal width! (1)Report the least value of recovery to the nearest 1 %.NOTE 3The use of
41、 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 effective.9.2.4 Place a clamp assembly containing the compressedspecimen in a refrigerated box capable of maintainin
42、g atemperature of 206 2F (29 6 1.1C) for 22 h. (Note 3).Unclamp the assembly and remove the upper compressionplate, or carefully remove the specimen and transfer it to awooden surface in the refrigerated box. Allow the specimen torecover for1hat206 2F (29 6 1.1C). Measure therecovered width and calc
43、ulate the recovery as in 9.2.3.9.2.5 Place a clamp assembly containing the compressedspecimen in an oven conforming to Test Method D 573. Thetemperature shall be maintained at 212 6 2F (100 6 1.1C)for 70 h. Do not preheat the clamp assembly. Unclamp theassembly, carefully remove the specimen, and al
44、low it torecover at 73 6 4F (23 6 2.2C) on a wooden surface for 1h. Measure the recovered width and calculate the recovery as in9.2.3.9.3 Compression-Deflection Tests:9.3.1 Determine compression-deflection values using speci-mens prepared in accordance with Section 8. Measure thelength of each speci
45、men 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 nearest132 in. (0.8 mm). Measure the height ofthe contact area on both sides and at both ends (four measure-ments) with
46、 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 LC m
47、in and LC max by multiplying the contact areatimes 3 psi (20.68 kPa) and 35 psi (241.32 kPa), respectively.9.3.4 Place the specimen on its side in such a manner that aplane through both edges of the top surface of the seal shall beperpendicular to the platens. Close the platens until thedistance bet
48、ween them is slightly larger than the actual widthof the seal. Test in accordance with Method A of Test MethodD 575, except that the speed shall be 0.5 6 0.05 in. (13 6 1.3mm)/min, and the sheets of sandpaper are not used.9.3.5 Compress the specimen to LC max by observing theforce calculated in 9.3.
49、3. Immediately reverse at the same rateto the original distance between the platens. Repeat this cycletwo times for a total of three cycles. Record the compressedwidth of the seal obtained at both the LC min and LC max onthe compression portion of the third cycle by measuring thecompressed width of the seal at those forces calculated in 9.3.3.9.3.6 During the course of running the test described in9.3.4, the tendency of the top surface of the seal to becomemisaligned shall be observed. Misalignment of more than14 in.(6.3 mm) sha
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