Block shear and delamination performance of cross-laminated bamboo and timber: an experimental investigation

Summary

No reviewed summary yet. Read the abstract below or open the original publication.

Abstract

This study investigated the bond quality and durability of three-layer cross-laminated bamboo and timber (CLBT) products, consisting of bamboo mat-curtain panels (BMCP) and hem-fir sawn timber bonded with a single-component polyurethane adhesive, evaluated through block shear and delamination tests. Block shear strength from loading along the major and minor strength directions and wood failure percentage were measured under dry and vacuum-pressure-soak-dry (VPSD) conditions. Delamination tests, involving soaking and boiling treatments, assessed the delamination percentage. Internal swelling and shrinking stresses during VPSD treatment accumulated damage to the bond lines, reducing block shear strength by 20–40%. CLBT specimens showed block shear strength that was 1.1–1.9 times higher when the hem-fir layers were loaded parallel to the grain rather than perpendicular to the grain. Both the VPSD and the delamination tests caused severe deterioration and delamination within the BMCP, hampering its potential for engineering applications. Due to the pronounced differences in structure between hem-fir lumber and BMCP, CLBT specimens exhibited paradoxical behaviour, showing a relatively high wood failure percentage of approximately 70% under VPSD treatment but a comparatively low delamination percentage of approximately 25% under the second-cycle boiling treatment, whereas the corresponding values for cross-laminated timber were approximately 60% and 40%, respectively.

Abstract as supplied by the source. Full text may be restricted by the publisher.