A Method for Predicting Non-Shear Compliances in the RT Plane of Wood
Keywords:Compliance, Young's modulus, Poisson's ratio, stress, strain
AbstractEquations were obtained relating the non-shear compliances in the radial-tangential, RT, plane to each other for a variety of hardwood and softwood species that were at 10 to 12% moisture content. From loadings made on short columns in the tangential, T, direction SRT = -0.255STT + 0.659 x 10-6; for loadings made on columns in the radial, R, direction STR = -0.887SRR - 1.260 x 10-6. In the compliance term Sij, "i" signifies the direction of the observed strain and "j" the direction of the applied stress; i.e., SRT relates strain in the R direction to stress in the T direction. Since SRT = STR for orthotropic materials, it follows that SRR = 0.291STT - 2.188 x 10-6. SRR and STT are entered as negative quantities in the above equations to indicate compression. Units for strain are inches per inch and for stress are pounds per square inch. These equations should be useful for finite element studies in mechanics and for studies on strains developed during wood drying.
Beery, W. H., G. Ifju, and T. E. McLain. 1983. Quantitative wood anatomy—Relating anatomy to transverse tensile strength. Wood Fiber Sci. 15(4):395-407.nBodig, J., and J. R. Goodman. 1969. A new apparatus for compression testing of wood. Wood Fiber 1(2):146-153.nBodig, J. and J. R. Goodman. 1973. Prediction of elastic parameters of wood. Wood Sci. 5(4):249-264.nBodig, J. and B. A. Jayne. 1982. Mechanics of wood and wood composites. Van Nostrand Reinhold Co. Inc., New York. 712 pp.nDoyle, D. V., J. T. Drow, and R. S. McBurney. 1945-1946. The elastic properties of wood. USDA Forest Service Report No. 1528; 1528 A-H. Forest Prod. Lab., Madison, WI.nGoodman, J. R., and J. Bodig. 1971. Orthotropic elastic properties of wood. J. Struct. Div., ASCE 96 (ST 11):2301-2319.nHearmon, R. F. S. 1948. Elasticity of wood and plywood. Forest Prod. Res. Spec. Report No. 7. His Majesty's Stationery Office, London. 87 pp.nKennedy, R. W. 1968. Wood in transverse compression: Influence of some anatomical variables and density on behavior. For. Prod. J. 18(3):36-40.nPanshin, A. J., and C. DeZeeuw. 1980. Textbook of wood technology. I. 4th ed. McGraw-Hill, New York.nSliker, A. 1967. Making bonded wire electrical resistance strain gages for use on wood. Forest Prod. J. 17(4):53-55.nSliker, A. 1971. Resistance strain gages and adhesives for wood. Forest Prod. J. 21(12):40-43.nSliker, A. 1972. Measuring Poisson's ratios in wood. Experimental Mechanics 12(5):239-42.nSliker, A. 1985. Orthotropic strains in compression parallel to grain tests. Forest Prod. J. 35(11/12):19-26.nSchniewind, A. P. 1959. Transverse anisotropy of wood: A function of gross anatomic structure. For. Prod. J. 9(10):350-360.n
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