A systematic review of the rolling shear modulus of timber

The rolling shear modulus of Cross-Laminated Timber (CLT) and other engineered timber governs the performance and stability. The study was systematically analyzed using rolling shear modulus tests on hardwoods and softwoods. Literature was searched in Scopus, Google Scholar, and Web of Science for papers on rolling shear modulus, timber, and structural applications. Articles were chosen based on their relevance, high methodological quality, and outcome clarity. The review reveals that values of rolling shear modulus were different between planar, short-span bending, and modified planar shear tests. Spruce and pine have a smaller value of rolling shear modulus as compared to beech and oak. This disparity emphasizes the need for standardized testing for reliable evaluations. An analysis of the results with respect to materials selection, and species-specific structural design in timber engineering is made presenting insights into rolling shear modulus. Findings reveal that the Iosipescu shear test to be the most recommended method for determining the rolling shear modulus of timber. This test directly measures the shear stress-strain response and provides more consistent and reliable results compared to other methods, such as the torsion test or the panel shear test.  Keywords: Rolling Shear Modulus, Timber Engineering, Cross-Laminated Timber, Hardwood, Softwood.