ISO INTERNATIONAL STANDARD 8906 First edition 1988-07-15 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION MEXKAYHAPOAHAROPIAHM3ALMRNOCTAHAAPTM3ALMM Sawn timber -- Test methods - Determination of resistance to local transverse compression Bois scies-Methodes d'essai-Determinationdela resistanceala compression localisee transversale Reference number ISO 8906:1988 (E) ISO8906:1988 (E) Foreword ISo (the International Organization for Standardization) is a worldwide federation of national standards bodies (Iso member bodies). The work of preparing International Standards isnormallycarriedoutthroughIsOtechnicalcommittees.Eachmember body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with Iso, also take part in the work. Iso collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. DraftInternationalStandardsadoptedbythetechnical committeesarecirculatedto the member bodies for approval before their acceptance as International Standards by the ISo Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 8906 was prepared by Technical Committee ISO/TC 55, Sawn timber and sawlogs. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. ? International Organizationfor Standardization,1988 Printed in;Switzerland INTERNATIONALSTANDARD ISO8906:1988 (E) Sawn timber - Test methods - Determination of resistance tolocaltransverse compression Scope and field of application 5 Preparation of test pieces This International Standard specifies a method of determining 5.1 The test piece, in the form of a right-sided prism of length the resistance of sawn timber of coniferous and broadleaved 150 mm and height 50 mm, shall be cut from areas nearest to species to local transverse compression. the edge of the sawn timber to be tested over the whole It does not cover testing of small defect-free test pieces of thickness, t (see figure 1). wood. The measured surfaces of the test piece (formed by the edge of the board and the edge opposite) shall be parallel. 2 Reference The test piece may be cut from the portions of sawn timber left after sampling for other tests. iSo3130,Wood 一 Determination of moisture content for physical and mechanical tests. Dimensions in millimetres Principle proportional limit and the load at a given deformation, and calculation of the stresses at these loads. 4. Apparatus 4.1 Test machine, with a device registering load increments of less than 100 N/mm and deformation of the test piece of less than 0,02 mm/mm. In the absence of such a machine with a registering device, a test machine measuring the load to an accuracy of ± 1 % and capable of maintaining the test rate specified in 6.2 shall be used. b 4.2 Device, capable of ensuring uniform loading of the test piece by means of a punch of width 50 mm and length at least 10mmgreaterthanthethicknessof the sawntimbertobe tested. The edges of the punch shall be rounded to a radius of 2 mm. t For machines without a registering device, the unit shall be equipped with an instrument capable of measuring the defor- Figure 1 - Test pieces mationofthetestpiecetoanaccuracyof0,o1mm. 5.2 To determine the minimum resistance value to local 4.3 Measuring instrument, to determine the width of the transverse compression, select the test pieces from the test piece to an accuracy of o,1 mm. weakest portions of the sawn timber to be tested; this can be determined either visually or by the results of mechanized 4.4 Equipmentforthedeterminationofmoisturecon- grading. Defects increasing the resistan