Nature of Compression Failure in Wood

Inelasticity of wood in compression is started by buckling of the external fibers of the material. These fibers are laterally supported by the adjacent internal fibers and may be considered miniature Euler columns of unknown length. The fiber-column failure stress is derived using energy methods. This critical stress is found t be a function of the material compression modulus of elasticity, the transverse material tension strength, and the ratio of fiber diameter to lateral fiber deflection at buckling. Five wood species were tested in direct compression. Transverse tension coupon tests were performed on the same material. Good agreement was found to exist between theory and test results.