Testing Small Wood Specimens In Transverse Compression

The standard test method recommended in ASTM Standard D143 for compression perpendicular to the grain does not measure pure compression. The results of small wood specimens tested in compression perpendicular to the grain may be influenced by macroscopic characteristics of the specimen or the test procedure. Pure compression tests were performed on wood and poly(methyl methacrylate) specimens measuring 0.12 to 1.56 inch in height. Young's modulus in transverse compression increased with specimen height. Yield stress was not affected by specimen height. However, an increase of specimen height resulted in a decrease of yield strain. These observations may be explained by surface roughness or non-parallelism of the specimen. The results are not unique to wood