A Method for Predicting Non-Shear Compliances in the RT Plane of Wood


  • Alan Sliker


Compliance, Young's modulus, Poisson's ratio, stress, strain


Equations 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.


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