Physical, mechanical and thermal properties of cross laminated timber made with coconut wood

摘要

The fundamental material properties of coconut wood cross-laminated timber (CLT) were experimentally evaluated with a focus on the effect of the lamination density. Considering the significant density variations across the coconut trunks, the CLT specimens were manufactured using the coconut wood laminations of four density ranges: 655 +/- 31 kg/m(3), 741 +/- 23 kg/m(3), 851 +/- 49 kg/m(3), and 972 +/- 30 kg/m(3). The average bonding shear strength (5.2-9.1 MPa), compressive strength (33.1-56.7 MPa), and thermal conductivity (0.153-0.264 W/m K) of coconut CLT specimens increased with their density. Furthermore, the temperature dependence of thermal conductivity of the proposed CLT was explored. The thermal conductivity of the coconut CLT linearly increased with the heating temperatures regardless of its density. In contrast, the thickness swelling properties were found to be roughly similar among the produced CLT panels (2.4 +/- 0.6%), while the average water absorption percentages (11-20%) were inversely related against the density. Considering that the average compressive strengths of coconut CLT panel were approximately twice larger than those of conventional softwood CLTs, while their highest thermal conductivity was still less than the half of structural concrete's lowest thermal conductivity, the coconut wood CLT could be potentially used in exterior wall systems from the structural and energy perspectives.