Torsional Shear Tests on Laminated Veneer Lumber Using a Universal-Type Test Machine

Abstract

This paper presents a study in which a universal-type test machine was configured to apply torsion load-to-failure to estimate the orthotropic shear strengths of full-size laminated veneer lumber (LVL). The objective of the study is to provide insight and detail to a lesser known torsion test setup, while at the same time estimating the torsional shear strength of 1.9E eastern species LVL, hitherto unknown. It was found that at large angles of twist of approximately 23° or more, the test apparatus experienced slippage at the bearings and had the potential to become unstable due to high lateral forces. This was not an obstacle for calculating the shear strength of LVL in this study, as it is a relatively noncompliant material, but likely would be an issue for more compliant materials. The mean in-plane and through-thickness plane shear strengths of 1.9E eastern species LVL were estimated to be in the range of 7.2–11.2 MPa and 5.9–7.3 MPa, respectively.