1、Designation:C114489(Reapproved 2011)Standard Test Method forSplitting Tensile Strength for Brittle Nuclear Waste Forms1This standard is issued under the fixed designation C1144;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 is used to measure the static splittingtensile strength of cylindrical specimens of brittle nuclearwas
3、te forms.It provides splitting tensile-strength data that canbe used to compare the strength of waste forms when tests aredone on one size of specimen.1.2 The test method is applicable to glass,ceramic,andconcrete waste forms that are sufficiently homogeneous(Note1)but not to coated-particle,metal-m
4、atrix,bituminous,orplastic waste forms,or concretes with large-scale heterogene-ities.Cementitious waste forms with heterogeneities 1 to 2mm and 60 HRC are required.Any permanent indentation of thebearing block invalidates the test.Suitable materials are toolsteels hardened from 60 to 65 HRC by conv
5、entional heattreatments and ground to obtain a smooth loading surface.Thesurfaces of the bearing blocks in contact with the pads shall beflat to within 60.03 mm,parallel within 60.03 mm/mm(1.7)measured on each of two perpendicular directions,and perpen-dicular to the loading axis within 60.03 mm/mm(
6、1.7).6.4 Pad MaterialsThe choice of pad material depends onthe strength and elastic modulus of the material tested.Asuitable pad material is one that prevents contact between thetest specimen and the bearing blocks but is soft enough todistribute the load over a small area.If the specimen andbearing
7、 block contact during the test(determined by visualinspection of the pad after testing),the test result is invalid.Ingeneral,balsa wood is a suitable pad material for testing glassand other materials with splitting tensile strengths less thanapproximately 100 MPa.The grain of the wood shall bealigne
8、d perpendicular to the line of contact between specimenand bearing block with the grain parallel to the bearing block.The thickness of the balsa wood shall be 1.6 6 0.2 mm(Note3).Fully annealed OFHC copper foil 0.13 by 0.01-mm thick(Note 3)is suitable for higher strength waste forms.NOTE3Deviations
9、in pad material sizes of this magnitude will notaffect test results.6.5 Load-Measurement SystemUse a strip-chart or x-yrecorder to obtain a record of the loading force versus time.The recorder must be capable of responding to sudden changesin load(response time 1 mm.Uncharacteristic minor chips or s
10、urface flaws(6 mm away from the loading points andonly if fracture does not initiate at these locations.If fractureoccurs at these locations,discard the results and repeat the test.Flaws as large as 1 mm are permitted on the flat surfaces onlyif they are at least 4 mm from the vertical diameter.Only
11、 flawssmaller than 0.1 mm are permitted within 4 mm of the verticaldiameter.9.Calibration and Standardization9.1 To ensure accuracy of stress calculations,the calibrationof the load-measurement system and specimen dimensionsmust be traceable to NIST standards.Enter and maintainrecords of calibration
12、s and dates of calibrations in laboratorynotebooks.A summary of applicable references is given inTable 2.10.Procedure10.1 Quality Assurance RequirementsThis proceduremust conform to all applicable quality assurance requirementsof the laboratory performing the test.10.2 Testing an Individual Specimen
13、:10.2.1 Record the room temperature.10.2.2 Record the specimen thickness and diameter to thenearest 0.01 mm and verify that each specimen is withinspecified dimensional tolerances(Section 8).Examine speci-men surface for flaws or chips 0.1 mm.10.2.3 Verify that bearing blocks are properly aligned(se
14、e6.3).10.2.4 Check load-measurement system with standardweights or an electrical method before testing using PracticeE4.Choose the full-scale load indication of the recorder so thatthe fracture load is indicated at a position that is 20%of fullscale.10.2.5 Position new pads for each test between the
15、 specimenand bearing blocks.Position the specimen on the lower padwith the flat surfaces parallel to the load axis.If flaws or chipsexist,position the specimens accordingly(see Section 8).Apply a light load(0.1 mm.11.3.2 Test ConditionsTabulate the dates of tests.Identifytest material,test temperatu
16、re,pad material,and the rationalefor its selection,test machine,and crosshead speed(mm/s).11.3.3 CalibrationDocument the date and procedure forcalibrations of the load cell,load-measurement system,andcaliper micrometer.Describe procedures used to determine thatspecimens and bearing blocks conformed to specifiedtolerances,flatness,and parallelisms.11.4 Fracture Strength Data:11.4.1 Test Specimen ResultsTabulate thickness and diam-eter(mm)for each specimen,fracture load(N)for each test,and calcula
