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The aim of this study was to investigate the shear performance of cross-laminated timber (CLT) and glulam made from densified Paraserianthes falcataria laminas. The densification process involved pre-treatment, compression with heat (105 °C, 6 MPa), and a cooling phase. CLT was manufactured from densified laminas of different thicknesses (24–60 mm), while glulam was produced from densified laminas that underwent pre-treatments of (1) pre-steaming (0–30 min) and (2) alkaline pre-treatment (sodium hydroxide (NaOH) concentrations: 0%–9%). Both CLT and glulam were cut into a pre-determined size before being subjected to a block shear test. The findings showed that the presence of pre-steaming (20 min) exhibited the highest shearing strength value. In contrast, alkaline pre-treatment reduced the shear performance of glulam. Here, 24 mm and 30 mm CLT were found to have the highest shearing strength among the parameters. Pre-steamed laminas showed better wettability, but no statistically significant correlation between the contact angle and shear strength of glulam. The densification process reduced the fiber pore areas of the laminas. The fiber pore areas with a shear strength of glulam, with or without alkaline pre-treatment, revealed a weak correlation. The correlation between fiber pore areas and the shear strength of CLT show no statistical significance. Here, 30 mm CLT with lowest moisture content and highest wood failure percentage exhibited a better bonding performance.

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Densification is a modification process commonly used to modify the density and hence, properties improvement of low-density wood. Cross-laminated timber (CLT) manufactured from plantation tree has gained more interest recently but the potentiality of using densified fast-grown plantation wood, Batai (Paraserianthes falcataria) in the layering of CLT has yet to be discovered. This study aims to investigate the relationship between morphology of densified wood and bending performance of lab-scale prototype CLT manufactured from it. Laminas after conditioned were hot-pressed (105°C, 6 MPa for 10 minutes) for two stages with venting (press released for 1 minute 40 seconds) in between before cooling to below 100°C to reduce immediate springback. Densified laminas with three different targeted thicknesses (8, 10, and 15) mm were produced before further manufactured into three-layer CLT (24, 30, and 45) mm thick panels. CLT 60 mm thick panels from three pieces of undensified (20 mm) laminas acts as control. Results show that area of pores morphologically had reduced significantly (average 6.59 µm2) for laminas densified to 8 mm. CLT 24 show significant improvement up to 696% (Modulus of Elasticity) and 48.8% (Modulus of Rupture) when the area of pores had reduced. Morphological of densified laminas correlates negatively with bending properties of CLT.

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