1、Designation: C120/C120M 15C120/C120M 15aStandard Test Methods of forFlexure Testing of Slate (Breaking Load, Modulus ofRupture, Modulus of Elasticity)Structural and Roofing Slate1This standard is issued under the fixed designation C120/C120M; the number immediately following the designation indicate
2、s the yearof original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONDue to the unique properties of slate, the fle
3、xure test is better adapted to use for strength andelasticity determinations than either compression or tension tests. Furthermore, several uses of slatesare such that these determinations are of special interest and value, besides furnishing comparativedata.The property of slate termed “grain” caus
4、es a slab of the material to break transversely in onedirection somewhat more readily than at right angles to this direction. For this reason it is desirableto test the strength and elasticity both parallel and perpendicular to the grain.Breaking load test results for samples of roofing slate under
5、this test method are only valid for thecommercial supply of slates of that thickness or greater. For the commercial supply of thinnerroofingsroofing slates, testing on samples of the minimum specified thickness must be conducted.When comparing roofing slates of equal thickness, but from various sour
6、ces, slates which meet therequired breaking load at the lowest specimen thickness will yield the best performance on the roofin terms of resistance to impact damage.The reliability of the data produced under this test method is largely influenced by the care andprotocol used in obtaining and prepari
7、ng the test specimens.1. Scope1.1 These test methods cover determination of the breaking load, modulus of rupture and modulus of elasticity of slate by meansof flexure tests.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in e
8、achsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It
9、is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C119 Terminology Relating to Dimension StoneC1799 Guide to Dimension Stone Test Spec
10、imen Sampling and Preparation3. Terminology3.1 DefinitionsAll definitions are in accordance with Terminology C119.1 These test methods are under the jurisdiction of ASTM Committee C18 on Dimension Stone and are the direct responsibility of Subcommittee C18.01 on Test Methods.Current edition approved
11、 Nov. 1, 2015Nov. 15, 2015. Published November 2015January 2016. Originally approved in 1925. Last previous edition approved in 20122015as C120/C120M-12.-15. DOI: 10.1520/C0120_C0120M-15.10.1520/C0120_C0120M-15A.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Cust
12、omer 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 th
13、e 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.Copyright A
14、STM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Significance and Use4.1 These test methods are useful in indicating the differences in flexure (breaking load, modulus of rupture, modulus ofelasticity) between various slates. These test method
15、s also provide one element in the comparison of slates.5. Apparatus5.1 Testing MachineThe accuracy of the testing machine shall be within 1 % for the range from 10 to 1000 lbf 50 to 5000N.5.2 Load Application and Support BlocksThe supports for the specimen shall be of the rocker type (Fig. 1) with t
16、he edgesat least as long as the width of the specimen. The load application block may be of either the rocker or rigid type. The portionsof the load application and support blocks contacting the stone shall be rounded, with a nominal radius of 12 in. 13 mm.6. Sampling6.1 Select the sample to represe
17、nt a true average of the type or grade of stone under consideration and of the quality suppliedto the market under the type designation to be tested. The sample may be selected by the purchaser or his authorized representativefrom the quarried stone or taken from the natural ledge and shall be of ad
18、equate size to permit the preparation of the desired numberof test specimens. When perceptible variations occur, the purchaser may select as many samples as are necessary for determiningthe variations in flexure (breaking load, modulus of rupture, modulus of elasticity).NOTE 1Refer to Guide C1799 fo
19、r additional information on selecting, preparing, and conditioning test specimens.FIG. 1 Specimens and Preferred Type of Loading Application and Support Blocks for Determining the Breaking Load, Modulus of Rup-ture Load and Modulus of ElasticityRupture of SlateC120/C120M 15a2BREAKING LOAD AND MODULU
20、S OF RUPTURE7. Test Specimens7.1 Structural or Electrical SlateSix representative specimens, 12 by 112 by 1 in. 300 by 40 by 25 mm in size, of theparticular slate under consideration shall be tested.7.2 Roofing SlateAt least ten specimens 4 in. 100 mm in width, 5 in. 125 mm or greater in length and
21、minimum 316 in.5 mm thick.1. Scope1.1 These test methods cover determination of the breaking load of roofing slate and modulus of rupture of structural slate byuse of simple three-point loading.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Th
22、e values stated in eachsystem may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associat
23、ed with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.8. Preparation of Specimens8.1 Structural or Electrical SlateSplit the slate for the test to a thickness of
24、 approximately 114 in. 30 mm and then saw intostrips 12 in. 300 mm in length by 112 in. 40 mm in width. Cut half of these with the length parallel to the grain and half withthe length perpendicular to the grain. Plane or rub down the 12 by 112-in. 300 by 40-mm faces to a thickness of approximately1
25、in. 25 mm, taking care to have the finished surfaces as nearly parallel as practicable.8.2 Roofing SlateCut one 4 by 5-in. 100 by 125-mm specimen from each of a minimum 10 shingles. The saw blade shallbe a continuous rim, diamond impregnated type, mounted to a water-cooled sliding bed saw capable of
26、 making a clean cut withno lacerated edges. Cut no part of the specimen nearer than 1 in. 25 mm to a sheared edge or nail hole. The 5 in. 125 mm orlonger dimension is to be measured and cut parallel with the long dimension of the slate shingle. Do not resurface the split faces.2. Referenced Document
27、s2.1 ASTM Standards:2C119 Terminology Relating to Dimension StoneC406 Specification for Roofing SlateC629 Specification for Slate Dimension StoneE4 Practices for Force Verification of Testing MachinesE145 Specification for Gravity-Convection and Forced-Ventilation Ovens3. Terminology3.1 DefinitionsA
28、ll definitions are in accordance with Terminology C119.4. Summary of Test Method4.1 Prepared and conditioned test specimens are placed on two support blocks in a test stand and loaded vertically at their centerpoint by a third block.5. Significance and Use5.1 These test methods are useful in indicat
29、ing the differences in flexure (breaking load, modulus of rupture) between variousslates. These test methods also provide one element in the comparison of roofing slates under Specification C406 and structuralslates under Specification C629.6. Apparatus6.1 Ventilated OvenConforming to the requiremen
30、ts of the applicable sections of Specification E145, and capable ofmaintaining a temperature of 140 6 4F (60 6 2C) and large enough to accommodate the test specimens.6.2 Testing Machine(see Fig. 1), conforming to the requirements of the applicable sections of Practices E4. The three-pointloading met
31、hod shall be used in conducting flexure tests employing support and loading blocks that will ensure that forces appliedto the beam sill be vertical only and applied without eccentricity. The apparatus should be capable of maintaining the span lengthand distances between the loading block and support
32、 blocks within 60.05 in. (61 mm). The load should be capable of beingC120/C120M 15a3applied at a uniform rate and in such a manner as to avoid shock. The accuracy of the testing machine shall be within 1 % for therange from 10 to 1000 lbf 50 to 5000 N and capable of being read to the nearest 5 lbf (
33、20 N).6.3 Load Application and Support BlocksThe supports for the specimens shall be of the rocker type (Fig. 1) with the edgesat least as long as the width of the specimen. The load application block may be of either the rocker or rigid type. The portionsof the load application and support blocks c
34、ontacting the specimen shall be rounded, with a nominal radius of 12 in. 13 mm.7. Conditioning7.1 Dry the specimens for 48 h in a ventilated oven (meeting the requirements of E145) at a temperature of 140 6 4F 60(606 2C.2C). At the 46th, 47th and 48th hour, weigh the specimens to ensure that the wei
35、ght is the same. If the weight continuesto drop, continue to dry the specimens until there are three successive hourly readings with the same weight. After removing thespecimens from the oven, cool them to room temperature in a desiccator prior to testing.10. Marking and Measuring10.1 On structural
36、or electrical slate, rule the center lines with a try-square perpendicular to the edges of the specimens.Likewise, rule the span lines, parallel to, and 5 in. 125 mm from, the center lines. On specimens of roofing slate rule the centerlines perpendicular to an edge that is parallel to the length of
37、the shingle. Rule span lines parallel to, and 1 in. 25 mm from, thecenter lines. Measure the specimen thickness at three points along the center line to the nearest 0.01 in. 0.1 mm and record theaverage as the specimen thickness.ROOFING SLATE BREAKING LOAD8. Sampling, Test Specimens, and Test Units8
38、.1 Select the sample to represent a true average of the slate shingles under consideration and of the quality supplied to themarket under the type designation to be tested. The sample may be selected by the purchaser, their authorized representative, orthe producer, from shingles fabricated from the
39、 quarried stone and shall be of adequate size to permit the preparation of the desirednumber of test specimens.8.2 Not less than ten specimens 4 in. 100 mm in width, 5 in. 125 mm or greater in length and minimum 316 in. 5 mm thickare required. When perceptible variations occur, as many samples as ar
40、e necessary may be selected for determining the variationin flexure.8.3 Cut one 4 by 5 in. 100 by 125 mm specimen from each shingle. The saw blade shall be a continuous rim, diamondimpregnated type, mounted to a water-cooled sliding bed saw capable of making a clean cut with no lacerated edges. Cut
41、no partof the specimen nearer than 1 in. 25 mm to a sheared edge or nail hole. The 5 in. 125 mm or longer dimension is to be measuredand cut parallel with the long dimension of the slate shingle. Do not resurface the split faces.8.4 Condition specimens in accordance with 7.1.9. Procedure9.1 Rule the
42、 center line with a try-square perpendicular to one of the 5 in. 125 mm edges of each specimen. Rule span linesparallel to, and 1 in. 25 mm from both sides of the center line.9.2 Measure the specimen thickness at three points along the center line to the nearest 0.01 in. 0.1 mm and record the averag
43、eas the specimen thickness.9.3 Measure the width of the specimen along the center line to the nearest 0.01 in. 0.1 mm and record this as the specimenwidth.9.4 The testing machine shall be accurate to 1 % within the range from 100 to 2000 lbf 500 to 10 000 N. Lay the specimensflatwiseLay the specimen
44、 flat on the rocker type support blocks as shown in Fig. 1.Apply the load at the center of the span througha rocker or fixed type load application block. When athe load of 10 lbf 10 lbf 50 N has been applied, stop the loading and makeall the blocks coincide with the marks on the specimen by centerin
45、g the specimen under the load application block and movingthe support blocks under the span marks. Apply loads at rates not exceeding 1000 lbf/min 5000 N/min until failure,failure andrecord the breaking load to the nearest 5 lbf 20 N.NOTE 2When all three load application and support blocks are of th
46、e rocker type, care must be taken to adjust all three until the top face of thespecimen is horizontal when loaded.NOTE 1When all three load application and support blocks are of the rocker type, care must be taken to adjust all three until the top face of thespecimen is horizontal when loaded.12. Ca
47、lculationStructural or Electrical Slate12.1 Calculate the modulus of rupture as follows:R 53Wl/2bd2! (1)C120/C120M 15a4where:R = modulus of rupture, psi MPa,W = breaking load, lbf N,l = span length between support blocks, in. mm,b = width of specimen at the center, in. mm, andd = thickness of specim
48、en at the center, in. mm.10. Report13.1 Structural or Electrical SlateReport all modulus of rupture values and the average of all modulus of rupture values forspecimens cut parallel to the grain as the modulus of rupture “across the grain.” Report all modulus of rupture values and theaverage of all
49、modulus of rupture values for specimens cut perpendicular to the grain as the modulus of rupture “with the grain.”All determinations shall be reported as information.10.1 Roofing SlateReport the span length, width of specimen, average thickness of specimen along the center line and at theedges and line, breaking load of each specimen. Thespecimen and average of the breaking loads shall be reported as the breakingload across the length of the slate shingle. loads. All dete
