Strands produced from small-diameter timbers of lodgepole and ponderosa pine were used to fabricate a composite sandwich structure as a replacement for traditional building envelope materials, such as roofing. It is beneficial to develop models that are verified to predict the behavior of these sandwich structures under typical service loads. When used for building envelopes, these structural panels are subjected to bending due to wind, snow, live, and dead loads during their service life. The objective of this study was to develop a theoretical and a finite element (FE) model to evaluate the elastic bending behavior of the wood-strand composite sandwich panel with a biaxial corrugated core. The effect of shear deformation was shown to be negligible by applying two theoretical models, the Euler–Bernoulli and Timoshenko beam theories. Tensile tests were conducted to obtain the material properties as inputs into the models. Predicted bending stiffness of the sandwich panels using Euler-Bernoulli, Timoshenko, and FE models differed from the experimental results by 3.6%, 5.2%, and 6.5%, respectively. Using FE and theoretical models, a sensitivity analysis was conducted to explore the effect of change in bending stiffness due to intrinsic variation in material properties of the wood composite material.

Dispersion curves for axially symmetric flexural waves in a circular aluminum plate were determined using both direct phase measurement and measurement of normal mode frequencies. Measurements were conducted with the 8 mm thick plate in air and with one surface loaded by water in an anechoic tank over a frequency range of 20–80 kHz. At frequencies larger than the critical frequency (at which the free plate flexural wave speed is equal to the sound speed in water) the phase speeds with the plate in air and in water are nearly equal and agree well with the Mindlin-Timoshenko theory. Below critical frequency, water loading causes significantly lower values, about fifteen percent here. The speed in the water-loaded plate appears to change abruptly at or just above the critical frequency, in reasonable agreement with the theory of Kurtze and Bolt [Acustica 9, 238–242 (1959)]. Significance of these results will be discussed. [Supported by the Naval Undersea Warfare Engineering Station, Keyport, WA.]