1、Designation:C120/C120M15aStandard Test Methods forFlexure Testing of Structural and Roofing Slate1This standard is issued under the fixed designation C120/C120M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revisio
2、n.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.INTRODUCTIONBreaking load test results of roofing slate under this test method are only valid for the commercialsupply of slates of that thicknes
3、s or greater.For the commercial supply of thinner roofing slates,testingon samples of the minimum specified thickness must be conducted.When comparing roofing slates of equal thickness,but from various sources,slates which meet therequired breaking load at the lowest specimen thickness will yield th
4、e 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 preparing the test specimens.1.Scope1.1 These test methods cover determination of the breakingload of
5、roofing slate and modulus of rupture of structural slateby use of simple three-point loading.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independe
6、ntly of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 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 standard to establish appro-priate safety and healt
7、h practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C119 Terminology Relating to Dimension StoneC406 Specification for Roofing SlateC629 Specification for Slate Dimension StoneE4 Practices for Force Verification of Testing Mac
8、hinesE145 Specification for Gravity-Convection and Forced-Ventilation Ovens3.Terminology3.1 DefinitionsAll definitions are in accordance with Ter-minology C119.4.Summary of Test Method4.1 Prepared and conditioned test specimens are placed ontwo support blocks in a test stand and loaded vertically at
9、 theircenter point by a third block.5.Significance and Use5.1 These test methods are useful in indicating the differ-ences in flexure(breaking load,modulus of rupture)betweenvarious slates.These test methods also provide one element inthe comparison of roofing slates under Specification C406 andstru
10、ctural slates under Specification C629.6.Apparatus6.1 Ventilated OvenConforming to the requirements of theapplicable sections of Specification E145,and capable ofmaintaining a temperature of 140 6 4F(60 6 2C)and largeenough to accommodate the test specimens.6.2 Testing Machine(see Fig.1),conforming
11、to the re-quirements of the applicable sections of Practices E4.Thethree-point loading method shall be used in conducting flexuretests employing support and loading blocks that will ensurethat forces applied to the beam sill be vertical only and appliedwithout eccentricity.The apparatus should be ca
12、pable ofmaintaining the span length and distances between the loadingblock and support blocks within 60.05 in.(61 mm).The load1These test methods are under the jurisdiction of ASTM Committee C18 onDimension Stone and are the direct responsibility of Subcommittee C18.01 on TestMethods.Current edition
13、 approved Nov.15,2015.Published January 2016.Originallyapproved in 1925.Last previous edition approved in 2015 as C120/C120M-15.DOI:10.1520/C0120_C0120M-15A.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMSt
14、andards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 should be capable of being applied at a uniform rate and insuch a manner as to avoid shock.The accu
15、racy of the testingmachine shall be within 1%for the range from 10 to 1000 lbf50 to 5000 N and capable of being read to the nearest 5 lbf(20 N).6.3 Load Application and Support BlocksThe supports forthe specimens shall be of the rocker type(Fig.1)with theedges at least as long as the width of the sp
16、ecimen.The loadapplication block may be of either the rocker or rigid type.Theportions of the load application and support blocks contactingthe specimen shall be rounded,with a nominal radius of12in.13 mm.7.Conditioning7.1 Dry the specimens for 48 h in a ventilated oven(meetingthe requirements of E145)at a temperature of 140 6 4F(606 2C).At the 46th,47th and 48th hour,weigh the specimensto ensure that the weight is the same.If the weight continues todrop,continue to dry the specimens until there