1、Designation: C 1352 96 (Reapproved 2008)Standard Test Method forFlexural Modulus of Elasticity of Dimension Stone1This standard is issued under the fixed designation C 1352; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、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 test method covers the procedure for determiningthe flexural modulus of elasticity of stone by using a simpleb
3、eam with quarter-point loading.1.2 Stone tests may be made with load applied perpendicu-lar to the bedding plane or rift and with load applied parallel tothe bedding plane or rift.1.3 Stone tests may be made for wet and dry specimenconditions.1.4 The specifier of the test shall determine which condi
4、-tions shall be used.1.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.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 this stan
5、dard 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:C119 Terminology Relating to Dimension StoneC 880 Test Method for Flexural Strength of DimensionStoneE4 Practices for Force Ver
6、ification of Testing Machines3. Terminology3.1 DefinitionFor definitions of terms used in this testmethod, refer to Terminology C119.3.2 Definitions of Terms Specific to This Standard:3.2.1 modulus of elasticity, nstress per unit strain, alsoknown as Youngs Modulus.4. Significance and Use4.1 This te
7、st method is useful for providing engineeringvalues for stress and deflection analysis of stone panels. It isalso useful in indicating the differences in flexural modulus ofelasticity between various dimension stones and stones of thesame type in different loading directions (parallel and perpen-dic
8、ular to rift or bedding planes).5. Apparatus5.1 Testing Machine (see Fig. 1), conforming to the require-ments of the applicable sections of Practices E4. The quarter-point loading method shall be used in making flexure tests ofstone employing bearing blocks that will ensure that forcesapplied to the
9、 beam will be vertical only and applied withouteccentricity. The apparatus should be capable of maintainingthe span length and distances between load-applying blocksand support blocks constant within 6 1.3 mm (6 0.05 in.). Theload should be capable of being applied at a uniform rate andin such a man
10、ner as to avoid shock.5.2 Deflection Gages, capable of reading to 0.002 mm(0.0001 in.) shall be used to measure mid-span deflections atthe two free edges and support deflections at each end.6. Test Specimens6.1 The test specimens shall measure 100 mm (4 in.) wideby 32 mm (1.25 in.) thick by 380 mm (
11、15 in.) long with a spanas tested of 320 mm (12.5 in.). The sides of the specimens shallbe at right angles with the top and bottom. The specimens shallhave a fine abrasive finish on the planes perpendicular to theload and a fine saw finish on the other four planes. Thedimensions of the specimen shal
12、l be measured and recorded tothe nearest 0.2 mm (0.01 in.). A minimum of five specimensshall be tested for each condition of test. The average valuecalculated from plots of the test results is reported as theflexural modulus of elasticity for that condition.6.2 Where the job thickness has been set (
13、the thickness ofthe stone panels for the project has been established), it is oftenrequested to perform flexural modulus of elasticity tests at thejob thickness. The following shall govern the specimen sizewhere it is requested to test at the job thickness, and the jobthickness is other than 32 mm (
14、1.25 in.). The span as testedshall be ten times the thickness. The specimen lengths shall benot less than 50 mm (2 in.) and not more than 100 mm (4 in.)greater than the span as tested. Where the thickness is less than70 mm (2.67 in.), the width of the specimen shall be 100 mm(4 in.). Where the thick
15、ness is greater than 70 mm (2.67 in.) thewidth shall be 1.5 times the thickness. Where the thickness is1This test method is under the jurisdiction of ASTM Committee C18 onDimension Stone and is the direct responsibility of Subcommittee C18.01 on TestMethods.Current edition approved Oct. 1, 2008. Pub
16、lished December 2008. Originallyapproved in 1996. Last previous edition approved in 2002 as C 1352-96(2002).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.other than 32 mm (1.25 in.) and the specimen size is inaccordance with the jo
17、b thickness criteria noted in the forego-ing, the average value of the test results for each condition shallbe reported as the flexural modulus of elasticity of the stone atthe job thickness for that condition. All other requirementsshall be in accordance with 6.1.6.3 Where the job surface finish ha
18、s been set (the architec-tural finish on the panels for the project has been established),it is often requested to perform flexural modulus of elasticitytests on specimens with the finish the same as on the job. Thefollowing shall govern when it is requested to test at the jobsurface finish. The spe
19、cimens shall have a finish on one planeperpendicular to the load in accordance with the finish speci-fied for the job. Unless there are data to the contrary, thepositioning of the specimen shall be with the finished face inflexural tension. The average value of the test results for eachcondition sha
20、ll be reported as the flexural modulus of elasticityof the stone at the job surface finish for that condition.All otherrequirements shall be in accordance with 6.1 and 6.2.6.4 Where the specimens conform to the requirements of 6.2and 6.3, the average value calculated from plots of the testresults fo
21、r each condition shall be reported as the flexuralmodulus of elasticity of the stone at the job thickness andsurface finish for that condition.7. Conditioning7.1 For specimens with uneven surfaces, prepare flat bear-ing areas for the span supports and quarter point loading blocksby applying a water
22、resistant capping compound 15 mm (12 in.)wide centered on these areas. Allow the capping compound todry or cure per the manufacturers recommendations beforecontinuing conditioning the specimens in accordance with 7.2or 7.3.7.2 Before testing the specimens in a dry condition, drythem for 48 h at 60 6
23、 2C (140 6 4F). At the 46th, 47th, and48th h, weigh the specimens to ensure the weight is the same.If the weight continues to drop, continue to dry the specimensuntil there are three successive hourly readings with the sameweight. After removing the specimens from the oven, coolthem to room temperat
24、ure in a desiccator before testing.7.3 Before testing the specimens in a wet condition, im-merse them in water for 48 h at 22 6 2C (72 6 4F). Testthem immediately upon removal from the bath, wiping thespecimens free of surface water.8. Procedure8.1 Assemble the apparatus, place the specimen on the s
25、pansupports, and adjust the quarter-point loading blocks intocontact with the specimens.8.2 Preload the specimen twice to a maximum load corre-sponding to 50 % of the anticipated ultimate strength and thenback to zero (Note 1). Increase the load at a rate thatcorresponds to a change in flexural stre
26、ss no greater than 4.14MPa (600 psi) per min.NOTE 1Ultimate flexural strength values are best determined by TestMethod C 880.8.3 Apply a preload of 44 N (10 lbf), zero the deflectiongages, and load reading apparatus (see Note 2).8.4 Increase the load in increments of approximately 10 %of the anticip
27、ated failure load. Stop the loading at eachincrement and record both of the two sample midspan edgedeflections. Continue load increments and deflection readingsuntil failure of the specimen occurs.NOTE 2It is frequently difficult to set the deflection gages to read zerowhen there is no load on the s
28、pecimen. A common practice is to apply asmall initial load to the specimen such as 44 N (10 lbf) and set thedeflection gages to read zero for this load. Since it is only the slope of thestress-strain curve that is desired, this initial load does not affect the finalresult.9. Calculation9.1 Plot the
29、load-deflection readings to a convenient scaleusing the average net midspan deflection and draw a straightline to represent, as nearly as possible, the average of theplotted points for the linear portion of the curve. (See Fig. 2.)If the line does not pass through the zero point, draw acorrected lin
30、e through this point and parallel to the stress-strainline. Calculate the flexural modulus of elasticity, E, from thecoordinates of a convenient Point A on the corrected line asfollows:E 511WL364Dbd3(1)FIG. 1 Diagrammatic View of a Suitable Apparatus for Flexural Modulus of Elasticity of Stone TestC
31、 1352 96 (2008)2D5SDc11Dc22D2SDs11Ds22Dwhere:E = flexural modulus of elasticity, MPa (psi),W = total load applied to specimen, N (lbf),W8 = load coordinate of the point, N (lbf),D = average net midspan deflection, mm (in.),Dc1= midspan deflection 1, mm (in.),Dc2= midspan deflection 2, mm (in.),Ds1=
32、support deflection 1, mm (in.),Ds2= support deflection 2, mm (in.),D8 = deflection coordinate of the point, mm (in.),L = span, mm (in.),b = width of specimen, mm (in.), andd = depth of specimen, mm (in.).10. Report10.1 The report shall include the following:10.1.1 Stone type and finish,10.1.2 Sizes
33、of the specimens used,10.1.3 Direction of bedding plane or rift,10.1.4 Preconditioning procedure used,10.1.5 Individual test results for each specimen, includingloads, deflections, and plots,10.1.6 Average value of the calculated test results for eachcondition of test using the following relation,E5
34、sum of observed valuesnumber of tests(2)10.1.7 Standard deviation, s, of the test results for eachcondition of test using the following relation, ands 5=sum of value 2 E!2number of tests 2 1(3)10.1.8 Any variations from the above procedural tech-niques.11. Precision and Bias11.1 Individual variation
35、s in a natural product may result indeviation from accepted values. A precision section will beadded when sufficient data are available to indicate acceptabletolerances in repeatability and reproducibility.12. Keywords12.1 dimension stone; flexure; modulus of elasticity; stoneASTM International take
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37、ponsibility.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 or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be address
38、ed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the
39、 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 reprints (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).FIG. 2 Typical LoadDeflection PlotC 1352 96 (2008)3
