Evaluation of the bonding process and interlaminar shear properties of hybrid cross-laminated timber prepared with larch and OSB

Abstract

This study explores the application of oriented strand board (OSB) to hybrid cross-laminated timber (HCLT). OSB and larch were used to prepare hybrid forms of HCLT for annlysis. Firstly, the effect of OSB surface treatment on the properties of the bonding line between materials was studied, including the surface properties of OSB before and after surface treatment. Block shear testing and cyclic delamination testing were used to study the bonding properties. The test results showed that suitable sanding can enhance the bonding performance. The optimal surface treatment process for OSB in this paper was found to be sanding at 0.2 mm depth. Secondly two layups of HCLT were prepared by combining OSB with larch, and the interlaminar shear strength was assessed in both the major and minor strength directions using a three-point bending test. The results showed that, due to the low density and mechanical properties of OSB, its application in HCLT as perpendicular layer is not a favorable choice, because it can not avoid the rolling shear failure in perpendicular layer, and it also reduces the interlaminar shear strength of HCLT in the minor strength direction. However, the interlaminar shear strength decreases in both the major and minor strength directions when OSB was used as the parallel layer, and larch was used as the perpendicular layer. Consequently, this improved the two-way carrying capacity of the HCLT plate.