ASTM D5365-2018 Standard Test Method for Long-Term Ring-Bending Strain of &x201c Fiberglass&x201d (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe.pdf

1、Designation: D5365 12D5365 18 An American National StandardStandard Test Method forLong-Term Ring-Bending Strain of “Fiberglass” (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe1This standard is issued under the fixed designation D5365; the number immediately following the designation indicates the

2、 year oforiginal adoption or, in the case of 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. Scope*1.1 This test method covers a procedure for determinin

3、g the long-term ring-bending strain (Sb) of “fiberglass” pipe. Bothglass-fiber-reinforced thermosetting-resin pipe (RTRP) and glass-fiber-reinforced polymer mortar pipe (RPMP) are “fiberglass”pipes.1.2 The values stated in inch-pound units are to be regarded as the standard. The SI units given in pa

4、rentheses are forinformation only.1.3 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 safety, health, and healthenvironmental practices and determine theapplica

5、bility of regulatory limitations prior to use. A specific warning statement is given in 9.5.NOTE 1There is no known ISO equivalent to this standard.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on

6、Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD1600 Terminology for Abbreviated Terms Relating to

7、PlasticsD3567 Practice for Determining Dimensions of “Fiberglass” (Glass-Fiber-Reinforced Thermosetting Resin) Pipe and Fittings3. Terminology3.1 Definitions:3.1.1 GeneralDefinitions are in accordance with Terminology D883 and abbreviations are in accordance with TerminologyD1600 unless otherwise in

8、dicated.3.2 Definitions of Terms Specific to This Standard:3.2.1 end pointthe failure of the test specimen. The failure mode may be catastrophic, characterized by a sudden fracturethrough the pipe wall in the area of greatest strain.3.2.2 fiberglass pipetubular product containing glass-fiber reinfor

9、cements embedded in or surrounded by curing thermosettingresin. The composite structure may contain aggregate, granular or platelet fillers, thixotropic agents, pigments, or dyes;thermoplastic or thermosetting liners or coatings may be included.3.2.3 reinforced polymer mortar pipe (RPMP)fiberglass p

10、ipe with aggregate.3.2.4 reinforced thermosetting resin pipe (RTRP)fiberglass pipe without aggregate.1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.23 on Reinforced Plastic PipingSystems and Chemical Equipment.Curre

11、nt edition approved April 1, 2012Aug. 1, 2018. Published May 2012August 2018. Originally approved in 1993. Last previous edition approved in 20062012 asD5365 - 06.D5365 - 12. DOI: 10.1520/D5365-12.10.1520/D5365-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Cu

12、stomer 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 an ASTM standard an indication of what changes have been made to

13、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 published by ASTM is to be considered the official document.*A Summar

14、y of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Summary of Test Method4.1 This test method consists of subjecting submerged-pipe ring specimens to various increasing deflectio

15、ns induced by aconstant load and monitoring the time to failure.Aminimum of 18 samples are required. Test temperatures are obtained by testingin a fluid environment where the temperature is controlled.4.2 The long-term ring-bending strain is obtained by an extrapolation to 50 years of a log-log line

16、ar regression line for failurestrain versus time.NOTE 2It is the consensus of Subcommittee D 20.23 D20.23 that the log-log linear regression analysis of test data is a conservative approach andis representative of standard industry practice. However, a task group has been formed to evaluate alternat

17、ive non-linear analysis methods.5. Significance and Use5.1 This test method determines the long-term ring-bending strain of pipe when deflected under constant load and immersed ina chemical environment. It has been found that effects of chemical environments can be accelerated by strain induced by d

18、eflection.This information is useful and necessary for the design and application of buried fiberglass pipe.NOTE 3Pipe of the same diameter but of different wall thicknesses will develop different strains with the same deflection.Also, pipes having the samewall thickness but different constructions

19、making up the wall may develop different strains with the same deflection.6. Apparatus6.1 Loading DeviceThe testing apparatus shall be suitable for maintaining a constant load on the test specimen.6.2 Load ApplicationThe load mayshall be applied to the test specimens using any of three alternative p

20、airs of parallel loadingsurfaces; flat plates, rods or bars of a length at least as long as the pipe ring and of sufficient strength and stiffness to ensure astraight loading surface throughout the test. The same type of loading device shall be used for each specimen in a test series. Inorder to ach

21、ieve uniform strain along the pipe, use 0.25-in. (6-mm) thick elastomeric pads between the parallel loading surfacesand the pipe ring (see Note 24).6.2.1 Flat PlatesThe plates shall have a minimum 6-in. (152-mm) width.6.2.2 BarsThe bars shall have a flat contact surface of 0.75 6 0.25 in. (19 6 6 mm

22、).6.2.3 RodsThe rod diameter shall be 2 6 0.25 in. (51 6 6 mm) for pipe rings 12 in. (305 mm) and greater in diameter. Forsmaller pipes, the rod diameter shall be 1 6 0.25 in. (25 6 6 mm).6.3 Environment ContainmentA test enclosure of sufficient size to fully immerse the test specimens shall be used

23、 to containthe test solution. The enclosure shall not chemically affect the test solution.NOTE 4Elastomeric pads with a hardness of Shore A40 to 70 have been used successfully.7. Test Specimens7.1 The test specimens shall be ring sections taken from a sample(s) of pipe selected at random from a norm

24、al production run.The test specimens shall have a minimum length of one nominal pipe diameter or 12 in. (305 mm) 6 5 %, whichever is less. Treatthe cut edges of the specimens by the same procedure as production products.8. Test Conditions8.1 The standard temperature shall be 23 6 5C (73.4 6 9F).9. P

25、rocedure9.1 Test Specimen Measurements:9.1.1 Wall ThicknessDetermine in accordance with Test Method D3567.9.1.2 Inside DiameterDetermine in accordance with Test Method D3567 at both ends prior to deflection and average themeasurements.NOTE 5It is recommended that the inside diameter be measured with

26、 the axis vertical.9.2 Place the test apparatus into the test enclosure.9.3 Place the pipe ring in the test apparatus (see Fig. 1) and apply force to deflect the specimen at a rate not to exceed 10 %of its diameter per minute while keeping the top and bottom loading devices (plates, bars, or rods) o

27、f the apparatus as near parallelas practical. When the desired deflection is obtained cease adding load to the apparatus.NOTE 6Alignment of the specimen within the loading devices is critical. The loading devices should not only be parallel with the load points 180opposite, but the pipe ring should

28、also be centered between the load-application guides.Additionally, the load-application guides should permit completevertical freedom of movement, so the specimen remains under constant load.9.4 Measure the vertical inside diameter of the deflected pipe specimen at both ends to the nearest 0.01 in.

29、(0.25 mm). Averagethe measurements and determine the initial deflection by subtracting the average vertical inside diameter after loading from themeasurement determined in 9.1.2.D5365 182NOTE 7Deflections in excess of 28 % of diameter may cause local flattening of the pipe and lead to erratic test r

30、esults. For deflections approaching28 %, improved accuracy is obtained by use of strain gages or by establishing, for each pipe product, a calibration of deflection versus measured strain.This calibration technique may also be useful at all deflection levels.9.5 Introduce the test solution to comple

31、tely submerge the pipe ring. The solution may be added prior to loading the pipe ringand should be added within 30 min of loading the pipe ring. Testing time commences only after both specimen loading (deflection)and the addition of solution are complete. (WarningSince the failure mode could be cata

32、strophic, take precautions to preventor contain splashing or spilling of the test solution or other damages resulting from the sudden collapse of the pipe specimen.)9.6 Periodically check and maintain the test solution within 65 % of the specified strength or concentration for the duration ofthe tes

33、t. The test specimen must remain completely submerged.NOTE 8As some solutions become more concentrated with the evaporation of water, care must be exercised in replenishment to prevent a build-upin strength. It may be necessary, with some reagents, to periodically clean the deflected specimen and re

34、place the test solution with a fresh mixture. Theuse of plastic film, cut carefully to fit around the test apparatus and floated on the top of the test solution, has been found helpful in reducing evaporation.9.7 Continuously monitor the decreasing pipe-ring inside vertical diameter versus time or i

35、nspect the loaded specimen at leastat the frequency given below and measure the pipe specimen inside vertical diameter:Hours Inspect at Least0 to 20 Every hour20 to 40 Every 2 h40 to 60 Every 4 h60 to 100 Every 8 h100 to 600 Every 24 h600 to 6000 Every 48 hAfter 6000 Every weekDetermine the deflecti

36、on by subtracting the inside vertical diameter from the measurement determined in 9.1.2.NOTE 9Decreasing diameter of the pipe ring (deflection change) may be monitored with an appropriate indicator on the apparatus above the solutionand submerged specimen.9.8 Calculate the end point (failure time an

37、d failure deflection) in accordance with 10.1.9.9 Record the following data:9.9.1 Average pipe-wall thickness,9.9.2 Average inside pipe diameter before deflection,9.9.3 Average inside pipe diameter after deflection,9.9.4 Initial deflection,9.9.5 Type of loading device,9.9.6 Type, location and time o

38、f any distress of the pipe wall,9.9.7 Failure deflection and time at the end point, and9.9.8 Type of failure.9.10 To determine the regression line and the lower confidence level, a minimum of 18 samples is required. Distribution of datapoints shall be as follows:Side View Front View1 Load-Applicatio

39、n Guides 5 Submerged Test Specimen2 Load-Application Device 6 Test Solution3 0.25 in (6 mm) Rubber Pad 7 0.25 in. (6 mm) Rubber Pad4 Test Enclosure 8 Load-Applicatiion DeviceFIG. 1 Long-Term Ring Bending Test ApparatusD5365 183Hours Failure Points10 to 1000 At least 41000 to 6000 At least 3After 600

40、0 At least 3After 10 000 At least 19.10.1 Those specimens that have not failed after more than 10 000 h may be included as failures to establish the regressionline. Use of these data points may result in a higher or lower extrapolated value.NOTE 10Non-failed specimens may be left under test and the

41、regression line recalculated as failures are obtained.10. Calculation10.1 Determine the failure time and deflection:10.1.1 The failure deflection and failure time shall be the last values noted prior to the fracture occurrence.10.2 Long-Term Ring-Bending Strain:10.2.1 Compute the failure strain for

42、each failed specimen as given in 10.2.1.1 and 10.2.1.2.10.2.1.1 Crown and invert failures:f 54.28e!f!D1f/2!2where:f = failure strain in inches per inch (millimetres per millimetre),e = wall thickness in inches (millimetres) in accordance with 9.1.1 (see Note 11),D = mean diameter in inches (millimet

43、res) (ID in accordance with 9.1.2 plus e in accordance with 9.1.1 or OD minus e), andf = failure deflection in accordance with 10.1.10.2.1.2 Springline failures:f 52.44e!f!D1f/2!2NOTE 11The Sb calculations assume that the neutral axis is at the pipe-wall midpoint. For pipe-wall constructions that pr

44、oduce an altered neutral-axisposition, it mayshall be necessary to evaluate results by substituting 2y for e. (y is the distance from the appropriate pipe surface to the neutral axis.)Neutral-axis position mustshall be determined with strain-gage couples.10.2.2 Use for each specimen in the series, t

45、he log of the failure strain and the log of the failure time in hours as described inA1.4.1. Calculate Sb, the strain at 50 years (438 000 h).10.2.3 If Sxy 0 (see Annex A1.4.2.2), consider the data unsuitable.10.2.4 Calculate r in accordance with A1.4.3.1. If r is less than the applicable minimum va

46、lue given in Table A1.1, considerthe data unsuitable.10.2.5 Prepare a graph on a log-log diagram showing time to failure versus failure strain, with time plotted on the horizontal(x) axis and strain on the vertical (y) axis.11. Reconfirmation of the Sb Regression Line11.1 When a piping product has a

47、n existing Sb regression line, any change in material, manufacturing process, construction orliner will necessitate a screening evaluation (reconfirmation) as described in 11.2, 11.3, 11.4, 11.5, and 11.611.5.11.2 Obtain failure points for at least two sets of specimens. Each specimen set shall cons

48、ist of three or more specimens testedat the same initial strain level, as follows:Hours to Failure(Average of Set)Failure Points10 to 200 At least 3More than 1000 At least 3Total: At least 6Include as failures those specimens that have not failed after 3000 h, provided they exceed the regression lin

49、e.11.2 Calculate and plot the 95 % confidence limits and the 95 % prediction limits of the original regression line in accordancewith A1.4.6.2 using only data obtained prior to the change.NOTE 12Prediction limits define the bounds for single observations, whereas confidence limits define the bounds for the regression line.NOTE 13For 95 % confidence limits, there is a 2.5 % probability that the mean value for the regression line may fall above the UCL and a 2.5 %probability that the mean value for the regression line may fall below the