MODELING OF PARALLEL-ALIGNED WOOD STRAND COMPOSITES

A growing number of structural composite wood products are currently a vailable commercially. These products are typically manufactured from small pieces of wood bonded with a synthetic resin under heat and pres sure. The development of these products has not been aided by the use of analytical models, but instead has resulted from expensive trial an d error manufacturing exercises. An analytical model capable of predic ting the tensile properties of a parallel-aligned strand composite was developed. Model development was aided by experimental data obtained from testing individual strands and small strand assemblies. The model , in computer form, incorporates a special finite element used to mode l the strands and resin of the composite, and uses a substructuring ro utine to take advantage of the composite's repeating nature. Experimen tal boards were manufactured and tested to check the validity of the m odel. Based on the experimental results, the model successfully predic ted the tensile stiffness and strength of the composite boards. This t ension model provides a sound foundation upon which further developmen t can be built. Further advancement of the model to allow prediction o f compression, and subsequently, bending properties is desirable. Even at this stage, however, the model could be a valuable tool to investi gate some of the many variables involved in product development.