Elastic properties of wood-strand composites with undulating strands

The following study examines the effects that undulating strands have on the elastic behavior of a wood-strand composite. A discrete Fourier series expansion was used to empirically describe the experimentally measured strand undulation paths. A fiber undulation model was used to predict elastic properties as a function of strand waviness using the empirical path descriptions. Strand undulation was shown to degrade Young's modulus of yellow-poplar laminates in both tension and compression, with more severe effects in compression. Experimental results from compression tests were in good agreement with the predictions based on the analytical model for maximum undulatory angles of 4 and 8°.