Production feasibility of nanoclay added cross laminated timber manufactured by using fir and pine woods

In this study the feasibility of production of nanoclay added cross laminated Scots pine and Uludag Fir lumber was carried out. After literature research and pilot studies, nanoclay was added with 1%, 2% and 4% ratios to PVAc D-3 glue and mixed thoroughly and compared with epoxy glued samples for control purpose. Cross laminated lumber boards were manufactured and cut for experiments with the dimensions of 3x6x44 and 2,5x6x44cm to determine rolling shear strength. 50% of the 2.5 cm width samples were also immersed in water and kept for 24 hours and their rolling shear properties were determined. In order to determine bending strength and modulus of elasticity, samples were cut with the dimensions of 2x6x44. Solid wood samples from each species were cut into 2 x 2x 10 cm and used for the determination of density and moisture contents. Also 2x2x6 cm samples were prepared for compression strength. The results of Rolling shear experiments on 3 cm wide samples, up to 21 % increase was obtained for Fir and 15 % increase was obtained for Scots Pine depending on nanoclay amount added to glue. However for epoxy glue same results were obtained for both species. For 2.5 cm wide specimens 22% increase on Fir and 21%increase for Scots Pine was obtained in terms of Rolling shear values. Half of the specimens immersed in water was destroyed because of delamination, the others gave 10 to 15% lower rolling shear values. Bending strength tests showed that 12% increase was found for nanoclay added Fir CLTs and 31% increase was found for nanoclay added Scots Pine CLTs compared to control specimens. Compression strength perpendicular to grain experiments revealed that up to 100% increase was obtained for Fir and 52 % for Scots Pine. According to the results increasing nanoclay amounts also increased rolling shear and compression strength values. Consequently, it was found that stronger wood structural elements can be manufactured by using nanoclay added PVAc glue. It can be said that nanoclay added CLT can found a place in wood construction industry.