Influence of Specimen Size on the Compressive Strength of Wood

Abstract

This study aimed to discuss the influence of specimen sizes on the compressive strength parameters of wood, specifically focusing on their compression strength, elastic modulus, and Poisson’s ratio. Therefore, three different-sized specimens (20 mm × 20 mm × 30 mm, 40 mm × 40 mm × 60 mm, 60 mm × 90 mm × 90 mm) were manufactured and tested in the longitudinal, radial, and tangential directions, following the standard testing method for acquiring the compressive strength of wood. Subsequently, based on the experimental results, compressive parameters, failure mechanisms, load–displacement curves, and stress–strain relationships were systematically analyzed for the three different-sized specimens. Meanwhile, the influence of specimen size on the compressive strength parameters of wood was also evaluated through finite element numerical simulations, utilizing the obtained mechanical parameters. The results revealed a significant correlation between compressive strength and specimen size, indicating a decrease in compressive strength with an increasing specimen size. Conversely, the elastic modulus and Poisson’s ratio exhibited less sensitivity to specimen size changes. Notably, the compressive strength parameters derived from small-sized specimens (20 mm × 20 mm × 30 mm) exhibited a lack of rationality, while those obtained from medium-sized (40 mm × 40 mm × 60 mm), and large-sized specimens (60 mm × 90 mm × 90 mm) demonstrated greater reliability, providing precise results in finite element numerical simulations.