Effects of combinations of lamina grade and thickness, and span-to-depth ratios on bending properties of cross-laminated timber (CLT) floor

Abstract

The aim of this study was to investigate effects of wood species, thickness and lamina combinations, and span-to-depth ratio (Rsd) on bending strength and stiffness of cross-laminated timber (CLT) floor element. CLTs with three different thickness (90 mm, 120 mm, and 150 mm) were manufactured using two species, larch and pine. Rsd was 12:1 for shear specimens and 24:1 for bending specimens. Four-point bending test was carried out in accordance with prEN 16351. The higher density species (larch) CLT showed higher load resistance with larger span length. The load resistances of larch CLT was 1.2 times higher than pine CLT. The maximum span length of larch CLT was 1.1 times longer than pine CLT. As the thickness of CLT was increased, load resistance and span length were also increased. When the thickness of CLT was increased from 90 mm to 150 mm, load resistances was increased by approximately 308% for larch and 310% for pine, and span length was increased by approximately 90% for larch and 89% for pine.