ASTM_C_121_-_C_121M_-_15.pdf

Designation:C121/C121M15Standard Test Method forWater Absorption of Slate1This standard is issued under the fixed designation C121/C121M;the number immediately following the designation indicates 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.INTRODUCTIONIt is often desirable to gain some idea of the porosity of a material in question.Actualdeterminations of the pore space require the use of rather elaborate and refined equipment as well asconsiderable precision in carrying out the tests.For comparative purposes the absorption test affordsa simple and sufficiently accurate means of obtaining the desired information.As applied to slate thistest requires somewhat more care and precision than many other materials because of its dense natureand,consequently,the small quantities to be dealt with.Furthermore,the cleavage of slatethatproperty which permits it to be split into thin sheets of uniform thicknessmust be taken intoconsideration when this test is made.On this account misleading results are often obtained on cubicalspecimens due to accidental cleavage cracks in the specimens.The shapes of specimens and largernumber of specimens recommended in the following procedure are intended to eliminate to a largeextent the inconsistent results which may be obtained on this material.1.Scope1.1 This test method covers the determination of the waterabsorption of slate.1.2 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system may not be exact equivalents;therefore,each system shall be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.3 This standard does not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to consult and establish appropriatesafety and health practices and determine the applicability ofregulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C119 Terminology Relating to Dimension StoneC1799 Guide to Dimension Stone Test Specimen Samplingand Preparation3.Terminology3.1 DefinitionsAll definitions are in accordance with Ter-minology C119.4.Significance and Use4.1 This test method is useful in indicating the differences inwater absorption of slates.This test method also provides oneelement in the comparison of slates.5.Test Specimens5.1 The test specimens shall consist of square or rectangularslabs from316to516in.5 to 8 mm in thickness and not lessthan 4 in.100 mm on any side.5.2 Not less than six specimens shall be prepared from eachsample of slate,the sample being considered as any number ofpieces selected to represent a definite part or grade of thedeposit.6.Sampling6.1 Select the sample to represent a true average of the typeor grade of stone under consideration and of the qualitysupplied to the market under the type designation to be tested.The sample may be selected by the purchaser or his authorizedrepresentative from the quarried stone or taken from the naturalledge and shall be of adequate size to permit the preparation ofthe desired number of test specimens.When perceptiblevariations occur,the purchaser may select as many samples asare necessary for determining the variations in water absorp-tion of slate.1This 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.15,2015.Published November 2015.Originallyapproved in 1925 as C12125T.Last previous edition approved in 2009 asC121091.DOI:10.1520/C0121_C0121M-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,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 NOTE1Refer to Guide C1799 for additional information on selecting,preparing,and conditioning test specimens.7.Preparation of Specimens7.1 Split the slate to the required thickness and saw to size.When the specimens are prepared from shingles no saw cutshall be nearer than 1 in.25 mm to the sheared edge of theshingle.7.2 Free the specimens from loose particles by scrubbingwith a fiber brush and clean water.8.Procedure,Preferred Method8.1 Dry the specimens for 48 h in a ventilated oven at atemperature of 140 6 4F 60 6 2C.At the 46th,47th,and48th hour,weigh the specimens to ensure that the weight is thesame.If the weight continues to drop,continue to dry thespecimens until there are three successive hourly readings withthe same weight.8.2 After drying,cool the specimens in the room for 15 minand then weigh.When