1、Designation: D2412 11Standard Test Method forDetermination of External Loading Characteristics of PlasticPipe by Parallel-Plate Loading1This standard is issued under the fixed designation D2412; 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This te
3、st method covers the determination of load-deflection characteristics of plastic pipe under parallel-plateloading.1.2 This test method covers thermoplastic resin pipe, rein-forced thermosetting resin pipe (RTRP), and reinforced poly-mer mortar pipe (RPMP).1.3 The characteristics determined by this t
4、est method arepipe stiffness, stiffness factor, and load at specific deflections.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.NOTE
5、 1While this test method can be used in measuring the pipestiffness of corrugated plastic pipe or tubing, special conditions andprocedures are used. These details are included in the product standards,for example, Specification F405.1.5 The text of this test method references notes andfootnotes that
6、 provide explanatory material. These notes andfootnotes (excluding those in tables and figures) shall not beconsidered as requirements of the test method.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of t
7、his standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D695 Test Method for Compressive Properties of RigidPlasticsD1600 Terminology forAbbreviated Terms Relating to Plas-ti
8、csD2122 Test Method for Determining Dimensions of Ther-moplastic Pipe and FittingsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodF405 Specification for Corrugated Polyethylene (P
9、E) Pipeand FittingsF412 Terminology Relating to Plastic Piping Systems3. Terminology3.1 DefinitionsDefinitions are in accordance with Termi-nology F412, and abbreviations are in accordance with Termi-nology D1600, unless otherwise specified.3.2 Definitions of Terms Specific to This Standard:3.2.1 ym
10、easured change of the inside diameter in thedirection of load application expressed in inches (millimetres).3.2.2 initial inside diameter (d)the average of the insidediameters as determined for the several test specimens andexpressed in inches (millimetres).3.2.3 load (F)the load applied to the pipe
11、 to produce agiven percentage deflection. Expressed as newtons per metre orpounds-force per linear inch.3.2.4 mean radius (r)the mid-wall radius determined bysubtracting the average wall thickness from the average outsidediameter and dividing the difference by two. Expressed asinches (millimetres).3
12、.2.5 pipe deflection (P)the ratio of the reduction in pipeinside diameter to the initial inside diameter expressed as thepercentage of the initial inside diameter.3.2.6 pipe significant events:3.2.6.1 liner cracking or crazingthe occurrence of a breakor network of fine breaks in the liner visible to
13、 the unaided eye.3.2.6.2 rupturea crack or break extending entirely orpartly through the pipe wall.1This test method is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.40 on TestMethods.Current edition approved April 1, 2011.
14、 Published April 2011. Originallyapproved in 1965. Last previous edition approved in 2010 as D2412 10a. DOI:10.1520/D2412-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、refer to the standards Document Summary page onthe ASTM website.*A Summary 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 StatesThis international standard was developed in accordance wi
16、th internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1NOTE 2The significant events listed may
17、or may not occur in aspecific pipe material.3.2.6.3 wall crackingthe occurence of a break in the pipewall visible to the unaided eye.3.2.6.4 wall delaminationthe occurrence of any separationin the components of the pipe wall visible to the unaided eye.3.2.7 pipe stiffness (PS)the value obtained by d
18、ividing theforce per unit length of specimen by the resulting deflection inthe same units at the prescribed percentage deflection.3.2.8 stiffness factor (SF)the product of pipe stiffness andthe quantity 0.149 r3.3.2.9 DiscussionThe “pipe stiffness” and “stiffness factor”are related as follows:PS 5 F
19、/y (1)SF 5 EI 5 0.149 Fr3/y 5 0.149 r3PS! (2)NOTE 3See Appendix X2 for information relating PS, E, and y.4. Summary of Test Method4.1 A short length of pipe is loaded between two rigidparallel flat plates at a controlled rate of approach to oneanother. Load-deflection (of the pipe diameter) data are
20、 ob-tained. If cracking, crazing, delamination, or rupture occurs,the corresponding load and deflection are recorded.5. Significance and Use5.1 The external loading properties of plastic pipe obtainedby this test method are used for the following:5.1.1 To determine the stiffness of the pipe. This is
21、 afunction of the pipe dimensions and the physical properties ofthe material of which the pipe is made.5.1.2 To determine the load-deflection characteristics andpipe stiffness which are used for engineering design (seeAppendix X1).5.1.3 To compare the characteristics of various plastics inpipe form.
22、5.1.4 To study the interrelations of dimensions and deflec-tion properties of plastic pipe and conduit.5.1.5 To measure the deflection and load-resistance at any ofseveral significant events if they occur during the test.6. Apparatus6.1 Testing MachineA properly calibrated compressiontesting machine
23、 of the constant-rate-of-crosshead movementtype meeting the requirements of Test Method D695 shall beused to make the tests. The rate of head approach shall be 0.506 0.02 in. (12.5 6 0.5 mm)/min.NOTE 4Hydraulic testing machines that may vary slightly from theserate limits are commonly used and are s
24、atisfactory for testing RTRP andRPMP pipe 24-in. (610-mm) size and larger.6.2 Loading PlatesThe load shall be applied to the speci-men through two parallel steel bearing plates. The plates shallbe flat, smooth, and clean. The thickness of the plates shall besufficient so that no bending or deformati
25、on occurs during thetest, but it shall not be less than 0.25 in. (6.0 mm). The platelength shall equal or exceed the specimen length and the platewidth shall not be less than the pipe contact width at maximumpipe deflection plus 6.0 in. (150 mm).NOTE 5For some types of testing machines a greater pla
26、te thicknessmay be required to limit plate bending.6.3 Deformation (Deflection) Indicator The change ininside diameter, or deformation parallel to the direction ofloading, shall be measured with a suitable instrument meetingthe requirements of Test Method D695, except that the instru-ment shall be a
27、ccurate to the nearest 0.010 in. (0.25 mm). Theinstrument shall not support the pipe test specimen or the plateor affect in any way the load deflection measurements.Changes in diameter are measured during loading by continu-ously recording plate travel or by periodically computing it.7. Test Specime
28、ns7.1 For thermoplastic pipe, the test specimen shall be apiece of pipe 6 618 in. (150 6 3 mm) long.7.2 For reinforced thermosetting resin pipe, the minimumtest specimen length shall be three times the nominal pipediameter or 12.0 in. (300 mm), whichever is smaller. For pipelarger than 60 in. (1524
29、mm) in diameter, the minimumspecimen length shall be 20 % of the nominal diameteradjusted to the nearest 1 in. (25.4 mm).7.3 The ends of specimens shall be cut square and shall befree of burrs and jagged edges.7.4 No less than three specimens shall be tested for eachsample of pipe.NOTE 6For quality
30、control testing a single specimen may be used withthe thinnest wall at the top.7.5 Certain RTRP pipes exhibit surface irregularity becausethe production process is inside diameter controlled. To assureaccurate test results by parallel-plate loading, the test specimenmust be uniformly loaded along it
31、s entire bearing surface. Ifsurface irregularities (resin-rich areas) along the outside diam-eter prevent the bearing load from being uniformly distributedalong the length of the specimen, the outside surface along theloading line shall be sanded smooth by hand. This sandingshall only be done if the
32、 reinforcement is not damaged. Notethat sanding shall be done only along the plate contact lines.8. Conditioning8.1 Condition pipe for at least4hinair,atatemperature of73.4 6 3.6F (23 6 2C), and conduct the test in a roommaintained at the same temperature.8.2 When a referee test is required, conditi
33、on specimens forat least 40 h at 73.4 6 3.6F (23 6 2C) and 50 6 5 % relativehumidity and conduct the test under the same conditions.9. Procedure9.1 Make the following measurements on each specimen:9.1.1 Determine the length of each specimen to the nearest132 in. (1 mm) or better, by making and avera
34、ging at least fourequally spaced measurements around the perimeter.9.1.2 Measure the wall thickness of each specimen inaccordance with Test Method D2122. Make at least eightmeasurements equally spaced around one end and calculate theaverage wall thickness.D2412 1129.1.3 Determine whether a line of m
35、inimum wall thicknessexists along the length of the specimen and if so mark it for usein 9.2.1.NOTE 7On RTRP and RPMP pipe measurements may be made at bothends.9.1.4 Determine the average outside diameter to the nearest0.01 in. (0.2 mm) using a circumferential wrap tape or byaveraging the maximum an
36、d minimum outside diameters asmeasured with a micrometer or caliper.9.1.5 For OD-controlled pipe calculate the average pipeinside diameter (ID) by subtracting two times the average of allwall thicknesses (9.1.2) from the average of all outsidediameters (9.1.4). For ID-controlled pipe determine the a
37、ver-age ID by measuring the maximum and minimum insidediameters. Use this average ID as the basis for computing thepercentage of deflection for all specimens in that lot of pipe.9.2 Locate the pipe section with its longitudinal axis parallelto the bearing plates and center it laterally in the testin
38、gmachine.9.2.1 If an orientation of minimum wall thickness has beenfound, place the first specimen so the thinnest wall is at the topand rotate successive specimens 35 and 70. If no minimumwall thickness was identified, use any base line.9.3 With the deflection indicator in place, bring the upperpla
39、te into contact with the specimen with no more load than isnecessary to hold it in place. This establishes the beginningpoint for subsequent deflection measurements.9.4 Compress the specimen at a constant rate of 0.50 6 0.02in. (12.5 6 0.5 mm)/min.NOTE 8For larger sizes of pipe made from relatively
40、low-modulusmaterials, creep may affect the results of this test because of the loadingrate specified.9.5 Record load-deflection measurements continuously orintermittently with reference to the relative movement of thebearing plates. If measurements are made intermittently, makeand record such measur
41、ements at increments of not more than5 % of the average inside diameter of the specimen. Refer toAnnex A1.9.6 Observe and note the load and deflection at the firstevidence of each of the following significant events when andif they occur:9.6.1 Liner cracking or crazing.9.6.2 Wall cracking.9.6.3 Wall
42、 delamination.9.6.4 Rupture.9.7 Record type and position of each event with respect tothe corresponding load and deflection. Discontinue the testwhen either of the following occur:9.7.1 The load on the specimen fails to increase withincreasing deflection (maximum point on load-deflection plothas bee
43、n reached).9.7.2 The specimen deflection reaches 30 % of the averageinside diameter or the required maximum deflection.10. Calculation10.1 Calculate the pipe stiffness, PS, for any given deflec-tion as follows:PS 5 F/y lbf/in./in. kPa! (3)NOTE 9Refer to Appendix X3 for additional information on unit
44、s.10.2 When required, calculate the stiffness factor, SF, forany given deflection as follows:SF 5 0.149 r3PS in.3lbf/in.2Pam3! (4)10.3 When required, calculate the percentage pipedeflection, P, as follows:P 5 y/d 3100 (5)11. Report11.1 Report the following information:11.1.1 Complete identification
45、of the material tested, includ-ing type, source, manufacturers code, previous history (ifany), and product identification by standard number.11.1.2 Dimensions of each specimen, including averageoutside diameter, average wall thickness, average insidediameter, liner thickness and reinforcement thickn
46、ess whereapplicable, and average length.11.1.3 Whether or not the outside diameter of the specimenwas sanded.TABLE 1 Pipe StiffnessPrecision StatisticsAMaterialDeflectionLevel, %Average SmeanSrBSRBr RStandardDeviation ofCell AveragesCRepeatabilityStandardDeviationCReproduce-abilityStandardDeviationC
47、RepeatabilityLimit (95 %)CReproduce-abilityLimit (95 %)CA 2.5 772.3 54.95 84.69 101.0 237.1 282.7 7.11 11.0 13.1 30.7 36.6B 2.5 380.2 20.52 18.12 27.37 50.72 76.64 5.40 4.77 7.20 13.3 20.2C 2.5 463.9 79.07 57.82 97.96 161.9 274.3 17.0 12.5 21.1 34.9 59.1A 5.0 755.7 33.30 80.30 86.93 224.8 243.4 4.41
48、 10.6 11.5 29.7 32.2B 5.0 356.1 19.13 15.32 24.51 42.89 68.62 5.37 4.30 6.88 12.0 19.3C 5.0 419.4 37.80 27.74 46.89 77.68 131.3 9.01 6.61 11.2 18.5 31.3A 7.5 724.8 27.85 76.14 81.07 213.2 227.0 3.84 10.5 11.2 29.4 31.3B 7.5 332.6 16.87 13.94 21.88 39.02 61.27 5.07 4.19 6.58 11.7 18.4C 7.5 371.7 26.7
49、0 18.82 32.66 52.69 91.45 7.18 5.06 8.79 14.2 24.6ATerms are used as specified in Practice E177.BSr= standard deviation of repeatability (variation of replicate samples by same laboratory).SR= standard deviation of reproducibility (variability between laboratory).CPrecision statistics as percent of average.D2412 11311.1.4 Conditioning temperature, time, and environment.11.1.5 The load and deflection at which any of the followingevents occurred:11.1.5.1 Liner cracking or crazing,11.1.5.2 Wall cracking,11.1.5.3 Wall delamination, and11.1
