ASTM D covers several procedures for testing the flexural properties of structural panels. These panels can be of different materials used to form plane structures such as floors, walls and ceilings. These materials can include plywood, particle board, strand board, veneer composites, and other wood type materials. Method B is a 4 point test with Two-Point Flexure in the middle of the board. Method C is a Pure Moment Test also known as a two point bend test.
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Designation: D — 00 e 1. Standard Test Methods for. Structural Panels in Flexure 1. A number in parentheses indicates the year of last reapproval. A superscript epsilon e indicates an editorial change since the last revision or reapproval. Structural panels in use include plywood, waferboard, oriented strand board, and composites of veneer and of wood-based layers. Four methods of tests are included:. The choice of method will be dictated by the purpose of the test, type of material, and equipment availability.
All methods are applicable to material that is relative uniform in strength and stiffness properties. Only Method C should be used to test material suspected of having strength or stiffness variations within a panel caused by density variations, knots, knot-holes, areas of distorted grain, fungal attack, or wide growth varia- tions.
However, Method B may be used to evaluate certain features such as core gaps and veneer joints in plywood panels where effects are readily projected to full panels. Method C generally is preferred where size of test material permits. An approximate correction can be made. Current edition approved Apr. Published July Originally published as D — Last previous edition D — It is equally well suited for testing uniform or clear material whenever specimen size is adequate.
It is preferred when equipment is available. This method uses a. The method is frequently used for quality assurance testing of oriented strand board. These errors are not present in Method C. It is the responsibility 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. Referenced Documents. Comparisons of results of plywood, veneer composites, and laminates with solid wood or other plywood constructions will be greatly assisted if the thickness of the individual plies is measured to permit compu- tation of section properties.
Control of Moisture Content. The test proceeds at a constant rate of. The depth of the specimen shall be equal to the thickness of material, and the width shall be 1 in.
When the principal direction of the face plies, laminations, strands, or wafers is parallel to the span, the length. D Note 3. To eliminate plate action when wider specimens are tested, the specimen width shall not exceed one third of the span length and precaution shall be taken to ensure uniform bearing across the entire width of the specimen at the load and reaction points.
N OTE 2—In cutting specimens to meet the length requirement, it is not intended that the length be changed for small variations in thickness. Rather, it is intended that the nominal thickness of the material under test should be used for determining the specimen length. Measure to the nearest 0. Measure width at mid-span to the nearest 0. N OTE 3—Establishment of a span-depth ratio is required to allow an accurate comparison of test values for materials of different thicknesses.
It should be noted that the span is based on the nominal thickness of the material and it is not intended that the spans be changed for small variations in thickness.
Design of end. Construction is shown in detail in Fig. Bearing points shall be rounded where they contact the specimen. Construction of a suitable end support using small roller. The use of a large ball bearing to provide lateral compensation for warp is also illustrated. This method is particularly recommended for thin specimens and small loads. For a discussion of these errors, their effects, and methods for reducing them, refer to Appendix X1.
Inch-Pound in. In cases where excessive local deformation may occur, suitable bearing plates shall be used. Radius of curvature of bearing plate or block shall not be so large as to cause bridging as the specimen bends. Calculate the rate of motion of the movable head as follows:. Choose increments of load so that not less than 12 and preferably 15 or more readings of load and. Similar requirements apply to the load axis.
Calculate specimen bending stiffness as follows:. It may be based on the entire cross section, may include only the moment of inertia of layers parallel to span, or may include all layers weighted in accor- dance with modulus of elasticity in the direction of bending stress. State clearly the method employed in the report. Width shall be 1 in. The alternate width is 12 in. Measurements shall be to the nearest 0. How- ever, it is important that the distance between load point and.
The alternate in. Material having high rolling shear strength or having all its plies, laminations, strands, or wafers parallel to span may use closer spacing between loads and supports. Other comments as well as those of 5. The axes of these surfaces shall remain parallel and at least one of them shall be free to turn about its axis or be loaded through rollers to prevent the application of friction forces to the surface of the specimen.
Construction of a satisfactory loading head is illustrated in Fig. Locate the pivot point that equalizes the two loads near the original neutral axis of the specimen.
A spacing of at least 24 and 12 times specimen thickness is recommended for specimens with the principal direction parallel and perpendicular to span respectively. All three points shall lie on the longitudinal axis of the specimen. Suitable equipment of the transducer type is illustrated in Fig. A dial gage could replace the transducer for manual reading. Remarks of 5. Method C—Pure Moment Test 7. Frames are free to move toward or away from each other during the test to preclude application of other than pure moments to the center span of the panel.
Rotational deformation between points near the ends of the arc is measured during the test by special sensing gages resting on pins projecting from the face of the panel at these points. Limitation on size may be imposed by equipment size or moment capacity or size of available material. When nonuniform material containing density variation, knots, knot-holes, sloping grain or other sources of large variability is tested for general construction and industrial use, a minimum specimen width of 24 in.
Measure width to the nearest 0. Apply equal and opposite pure moments to each end of the panel by frames. The frames shall be free to move toward or away from each other while under load to preclude application of direct tension or compression loads at large panel deformations. Support axes of the loading frames to remain in a parallel relationship throughout the test Note 4.
Space bars of the loading frames sufficiently to prevent shear failures between. A bar spacing of 20 times panel thickness is suggested to preclude most, if not all, shear failures in the plane of the panel. In some cases closer spacing may be entirely satisfactory. N OTE 4—These requirements dictate use of specialized equipment which may not be readily available. Until further innovations are made in pure bending test equipment, use of cable and pulley equipment of this type, either purchased or constructed at the laboratory, offers the only practical means of implementing this method.
This equipment is the subject of U. Patent No. Therefore, when panels 4 ft in width are to be tested, the horizontal force applied to one loading frame that is required to produce motion of both frames without a panel in the machine should not exceed 5 lb 2.
Where a cable and pulley system is employed, the use of cables of the smallest possible size consistent with loads, and relatively large pulleys will help minimize friction forces. N OTE 5—These limits are liberal in relation to conventional equipment in order to allow for laboratory fabrication and inexperience in the design of precision pure moment machines.
If gages are read, take at least 12 and preferably 15 or more readings below the approximate proportional limit. The characteristically violent failures of large panels will normally dictate removel of delicate measur- ing instruments from the panel when sufficient data in the elastic range has been obtained.
The angular rotation method uses special angular rotation measuring instruments to determine rotational deformation of the portion of the panel subjected to pure bending.
Reading of the dial gage to the nearest 0. An electronic transducer could be substituted for the dial gage for direct recording if system accuracy is adequate. One-eighth-inch three-millimetre pins. A reference rod approximately the same length as the spacing.
Use of linear differential transformers as trans- ducers permits primaries and secondaries to be wired to produce a single signal proportional to their sum for indication. EI 5 MR. Calculate the radius of curvature by the method discussed in 7. The depth of the specimen shall be the thickness of the panel.
ASTM D3043 Test Methods for Structural Panels in Flexure
Designation: D — 00 e 1. Standard Test Methods for. Structural Panels in Flexure 1. A number in parentheses indicates the year of last reapproval. A superscript epsilon e indicates an editorial change since the last revision or reapproval.
ASTM D3043 Flexural Structural Panel Testing Machine
Active view current version of standard. Other Historical Standards. More D Structural panels in use include plywood, waferboard, oriented strand board, and composites of veneer and of wood-based layers. Four methods of tests are included:.
ASTM D 3043 – 00 Structural Panels in Flexure
Historical Version s - view previous versions of standard. More D These properties are of primary importance in most structural uses of panels whether in construction for floors, wall sheathing, roof decking, concrete form, or various space plane structures; packaging and materials handling for containers, crates, or pallets; or structural components such as stress-skin panels. Conditioning of test material at controlled atmospheres to control test moisture content and determination of specific gravity are recommended.