Sample data, computation sheets, and cards have been incorporated, which were of assistance to the investigator in systematizing records. ASTM D This standard contains test methods for determining the various strength and elastic properties of wood through 11 different mechanical tests: Radial and Tangential Shrinkage. Certification Formally confirming that your products and services meet all trusted external and internal standards. When a weight is prescribed, the basic inch-pound unit of weight lbf and the basic SI unit of mass Kg are cited. Inspection Validating the specifications, value and safety of your raw materials, products and assets.
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These specimens shall be photographed in cross section and on the radial and tangential surfaces. Current edition approved Feb. Published April Originally approved in Last previous edition approved in as D DOI: No further reproductions authorized.
D 14 FIG. Tests shall be carried out in such manner that large changes in moisture content will not occur. To prevent such changes, it is desirable that the testing room and rooms for preparation of test specimens have some means of humidity control. The mechanical properties of wood are also affected by temperature alone. The temperature at the time of test shall in all instances be recorded as a specific part of the test record.
Record of Heartwood and Sapwood 7. Static Bending 8. The actual height and width at the center and the length shall be measured see These spans were established in order to maintain a minimum span-to-depth ratio of Both supporting knife edges shall be provided with bearing plates and rollers of such thickness that the distance from the point of support to the central plane is not greater than the depth of the specimen Fig.
The knife edges shall be adjustable laterally to permit adjustment for slight twist in the specimen Note 2. A block having a radius of in. If required for the purposes of the study, it shall be permitted to continue both loading and the loaddeflection measurement beyond the maximum load. NOTE 3One situation where the user may choose to continue the test and the load-deflection measurements beyond the maximum load is if the total energy under the flexural load-deflection curve is a parameter of concern.
In these instances for primary method specimens, it has been customary to continue the test and record the load-deflection curve beyond the maximum load to a 6 in. For secondary method specimens, it has been customary to continue loading to a 3 in. Alternatively, deflection may be taken relative to the tension surface at midspan. However, take care to ensure that vertical displacements which may occur at the reactions are accounted for. After the proportional limit is reached, less refinement is necessary in observing deflections.
It shall be permissible to continue the deflection measurement beyond the proportional limit using an alternative means of deflection measurement capable of at least a Class C rating when evaluated in accordance with Practice E D 14 minimum, the load-deflection curve shall be recorded at 0.
The fractured surfaces may be roughly divided into brash and fibrous, the term brash indicating abrupt failure and fibrous indicating a fracture showing splinters. Compression Parallel to Grain 9.
Similar apparatus is available for measurements of compression over a 2 in. With specimens of uniform cross section, this result can best be obtained when the ends are at a very slightly lower moisture content than the body. With green material, it will usually suffice to close-pile the specimens, cover the body with a damp cloth, and expose the ends for a short time.
For dry material, it may sometimes be advisable to pile the specimens in a similar manner and place them in a desiccator, should the failures in test indicate that a slight end-drying is necessary. NOTE 1The term cross grain shall be considered to include all deviations of grain from the direction of the longitudinal axis or longitudinal edges of the specimen. It should be noted that spiral grain may be present even to a serious extent without being evident from a casual observation.
NOTE 2The presence of cross grain having a slope that deviates more than 1 in 20 from the longitudinal edges of the specimen shall be cause for culling the test. The actual cross-sectional dimensions and the length shall be measured see At least one platen of the testing machine shall be equipped with a spherical bearing to obtain uniform distribution of load over the ends of the specimen. Load-compression readings shall be continued until the proportional limit is well passed, as indicated by the curve Note 5.
In case two or more kinds of failures develop, all shall be described in the order of their occurrence; for example, shearing followed by brooming. The failure shall also be sketched in its proper position on the data sheet. In determining the proportion of summerwood, it is essential that the end surface be prepared so as to permit accurate latewood measurement.
When the fibers are broomed over at the ends from sawing, a light sanding, planing, or similar treatment of the ends is recommended. Impact Bending The first drop shall be 1 in. For all other cases, a lbf 45 kg hammer shall be used. This record will also afford data from which the exact height of drop can be scaled for at least the first four falls. If the Toughness machine is used, the following procedure has been found satisfactory.
To aid in standardization and to facilitate comparisons, the size of the toughness specimen has been made equal to that accepted internationally. The load shall be applied to a radial or tangential surface on alternate specimens. Toughness Several types of machines such as the Toughness, Izod and Amsler have been used, but insufficient information is available to decide whether Adjust the machine before test so that the pendulum hangs vertically, and adjust it to compensate for friction.
Adjust the cable so that the load is applied to the specimen when the pendulum swings to 15 from the vertical, so as to produce complete failure by the time the downward swing is completed. Choose the weight position and initial angle 30, 45, or 60 of the pendulum, so that complete failure of the specimen is obtained on one drop.
Most satisfactory results are obtained when the difference between the initial and final angle is at least Compression Perpendicular to Grain The actual height, width, and length shall be measured see The actual width of the bearing plate shall be measured see Compression shall be measured between the loading surfaces.
Hardness The actual cross-sectional dimensions and length shall be measured see The projected area of the ball on the test specimen is 1 cm2.
Record the load at which the ball has penetrated to one half its diameter, as determined by an electric circuit indicator or by the tightening of the collar against the specimen. The choice between the two radial and between the two tangential surfaces shall be such as to give a fair average of the piece. The penetrations shall be far enough from the edge to prevent splitting or chipping Note Shear Parallel to Grain The actual dimensions of the shearing surface shall be measured see Apply the load to and support the specimen on end-grain surfaces.
The shear tool shall include an adjustable crossbar to align the specimen and support the back surface at the base plate. Take care in placing the specimen in the shear tool to see that the crossbar is adjusted, so that the edges of the specimen are vertical and the end rests evenly on the support over the contact area. Observe the maximum load only.
In all cases where the failure at the base of the specimen extends back onto the supporting surface, the test shall be culled. D 14 Deformation shall be measured over a 2 in. Take load-extension readings until the proportional limit is passed. Tension Perpendicular to Grain The actual width and length at minimum sections shall be measured see Cleavage The actual width and length at minimum section shall be measured see Tension Parallel to Grain The specimen shall be so oriented that the direction of the annual rings at the critical section on the ends of the specimens, shall be perpendicular to the greater crosssectional dimension.
The actual cross-sectional dimensions at minimum section shall be measured see Nail Withdrawal Bright diamond-point nails shall be used. All nails shall be cleaned before use to remove any coating or surface film that may be present as a result of manufacturing operations.
Each nail shall be used once. NOTE 17A fivepenny common nail meets this requirement. If difficulty is experienced with high-density woods in pulling the nails without breaking the heads, a sevenpenny cement-coated sinker nail with coating removed by use of a suitable solvent, may be used.
Two nails shall be driven on a tangential surface, two on a radial surface, and one on each end. The choice between the two radial and two tangential surfaces shall be such as to give a fair average of the piece. On radial and tangential faces, the nails shall be driven a sufficient distance from the edges and ends of the specimen to avoid splitting. The two nails on a radial or tangential face should not be driven in line with each other or less than 2 in.
After the test, a moisture section approximately 1 in. Fasten the specimens during the test in grips as shown in Figs. Observe the maximum load only Note NOTE 19Other test methods for determining specific gravity using specimens of different shape, size, and moisture content are found in Test Methods D In like manner, a carbon impression of the same end may be made after the specimen has been conditioned.
ASTM D143 PDF
ASTM D143 Timber Clear Specimen Test Equipment