THERMAL CONDUCTIVITY OF CROSS LAMINATED TIMBER (CLT) WITH A 45˚ ALTERNATING LAYER CONFIGURATION

Year 2020, Volume: 2 Issue: 1, 13 - 16, 30.06.2020

Hasan Öztürk , Duygu Yücesoy Semra Çolak

Abstract

Cross-laminated timber (CLT) has increasingly become a viable alternative to other structural materials, mainly because of its excellent properties related to sustainability, energy efficiency, and speed of construction. This has resulted in the recent emergence of a significant number of CLT buildings constructed around the world. Cross-laminated timber panels consist of lumber boards stacked and glued in layers, which run perpendicular to each other, making them dimensionally stable with high in- and out-of-plane strength and stiffness. Thermal conductivity is used to estimate the ability of insulation of material. Thermal conductivity of wood material has varied according to wood species, direction of wood grain, specific gravity, moisture content, resin type, and addictive members used in manufacture of wood composite panels. The aim of this study is the comparison of two types of CLT panels consisting of boards either with grain direction aligned at 45˚ or at 90˚, in terms of their insulation properties. In the study, spruce (Picea orientalis L.) was used as a wood species, and was used polyurethane for CLT panels. Thermal conductivity of CLT panels was determined according to ASTM C 518 & ISO 8301. As a result of this study, it was indicated that thermal conductivity values for 90˚ layers were higher than the values for 45˚ layers.

Keywords

Cross-laminated Timber, Grain Direction, Spruce, Thermal Conductivity

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