ASTM_D_3914_-_02_2016.pdf

Designation:D391402(Reapproved 2016)Standard Test Method forIn-Plane Shear Strength of Pultruded Glass-ReinforcedPlastic Rod1This standard is issued under the fixed designation D3914;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year 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 determination of the in-plane shear strength of pultruded,glass-fiber reinforced,ther-mosetting plastic rod of diameters ranging from 19 to 32 mm(34to 114in.).1.2 The values stated in SI units are to be regarded as thestandard.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 health practices and determine the applica-bility of regulatory limitations prior to use.Specific precau-tionary statements are given in Note 2 and Note 3.NOTE1There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD695 Test Method for Compressive Properties of RigidPlasticsE4 Practices for Force Verification of Testing Machines3.Terminology3.1 Definitions:3.1.1 in-plane shear strengththe shear strength at maxi-mum load in which the plane of fracture is centrally locatedalong the longitudinal axis of the specimen between twodiametrically opposed notches machined halfway through itsdiameter.4.Summary of Test Method4.1 In-plane shear strength,as determined by this testmethod,is measured by applying a compressive load tonotched cylindrical specimens of the type shown in Fig.1.Loading of the specimen is accomplished with a subpress,orcompression tool,such as those shown in Fig.1 and Fig.2 ofTest Method D695.Failure of the specimen occurs in shearbetween two centrally located notches,diametrically opposedand machined halfway through its diameter at a fixed distanceapart.The notches are accurately machined in the specimenwith maximum reproducibility by means of a special notchingjig(Fig.2a and Fig.2b)designed specifically for this purpose.5.Significance and Use5.1 Shear tests of various kinds are widely used in thereinforced plastics industry to assess the strength of thereinforcement-to-resin bond in polyester-,vinyl ester-,andepoxy-resin composites.In addition to their importance for thegeneration of data for research and development,qualitycontrol,and specification purposes,such tests are of fundamen-tal value to the fibrous reinforcement industry,since they canbe used to determine the potential of new sizing systems for thesurface treatment of glass fibers.5.2 The in-plane shear strength of pultruded cylindricalcomposites is an important property from an engineeringstandpoint,since pultruded rod,as such,is used in manystructural applications.6.Apparatus6.1 Testing MachineAny suitable testing machine capableof control of constant-rate-of-crosshead movement and com-prising essentially the following:6.1.1 Drive MechanismA drive mechanism for impartingto the movable member a uniform,controlled velocity withrespect to the stationary member,as required in 10.3.6.1.2 Load IndicatorA load-indicating mechanism ca-pable of showing the total compressive load carried by the testspecimen.The mechanism shall be essentially free of inertiallag at the specified rate of testing and shall indicate the loadwith an accuracy of 61%of the maximum indicated value ofthe test(load).The accuracy of the testing machine shall beverified at least once a year in accordance with Practices E4.6.1.3 Notching JigAnotching jig of the type shown in Fig.2a and Fig.2b,or the equivalent,for notching the testspecimens.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-ting Plastics.Current edition approved April 1,2016.Published April 2016.Originallyapproved in 1980.Last previous edition approved in 2008 as D3914-02(2008).DOI:10.1520/D3914-02R16.2For 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 6.1.4 Compression ToolA compression tool for applyingthe load to the test specimen,such as those shown in Fig.1 andFig.2 of Test Method D695.6.1.5 MicrometersSuitable micrometers,reading to 0.025mm or 0.001 in.,for measuring the diameter of the specimen,as well as the depth of,and distance between,the notches.7.Test Specimens7.1 ConfigurationTest specimens shall be carefully ma-chined from the rod sample of interest and shall conform to theshape and dimensions gi