Значение и использование

These methods cover tests on small clear specimens of wood that are made to provide the following:

4.1.1 Data for comparing the mechanical properties of various species,

4.1.2 Data for the establishment of correct strength functions, which in conjunction with results of tests of timbers in structural sizes (see Methods D 198 and Test Method D 4761), afford a basis for establishing allowable stresses, and

4.1.3 Data to determine the influence on the mechanical properties of such factors as density, locality of growth, position in cross section, height of timber in the tree, change of properties with seasoning or treatment with chemicals, and change from sapwood to heartwood.

Область применения

1.1 These methods cover the determination of various strength and related properties of wood by testing small clear specimens.

1.1.1 These methods represent procedures for evaluating the different mechanical and physical properties, controlling factors such as specimen size, moisture content, temperature, and rate of loading.

1.1.2 Sampling and collection of material is discussed in Practice D5536. Sample data, computation sheets, and cards have been incorporated, which were of assistance to the investigator in systematizing records.

1.1.3 The values stated in inch-pound units are to be regarded as the standard. The SI values are given in parentheses and are provided for information only. When a weight is prescribed, the basic inch-pound unit of weight (lbf) and the basic SI unit of mass (Kg) are cited.

1.2 The procedures for the various tests appear in the following order:

SectionsPhotographs of Specimens5Control of Moisture Content and Temperature6Record of Heartwood and Sapwood7Static Bending8Compression Parallel to Grain9Impact Bending10Toughness11Compression Perpendicular to Grain12Hardness13Shear Parallel to Grain14Cleavage15Tension Parallel to Grain16Tension Perpendicular to Grain17Nail Withdrawal18Specific Gravity and Shrinkage in Volume19Radial and Tangential Shrinkage20Moisture Determination21Permissible Variations22Calibration23

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.