Behavior of Sandwich Timber Slabs with a Core Formed by Bio-Plastic Fiber Using 3D Printing Technology

This research investigates the behavior of laminated wood panels with a core structure fabricated using 3D printing technology from bio-based plastic filament (Polylactic acid, PLA). The study of the effects of fiber printing angles and found that PLA+ printed in the direction parallel to the load (0 degrees) exhibits higher tensile and compressive strength than PLA+ printed at a 45-degree angle to the load by 17.92% and 12.81%, respectively. The study examines the mechanical properties of three types of PLA, including PLA-CF (Carbon fiber), PLA-GF (Glass fiber), and PLA+ (Plus). It was found that PLA+ has a tensile and compressive strength per unit material cost higher than PLA-CF by 35.62% and 22.83%, respectively, and higher than PLA-GF by 43.11% and 43.87%, respectively. PLA+ printed in the 0-degree direction (parallel to the load) was selected as the core material for the sandwich structure, which was fabricated with two core configurations: honeycomb and honeycomb lattice and sandwiched between bamboo layers on the top and bottom. The bending strength test results indicated that the structure with a honeycomb core had a bending strength-to-weight ratio 1.8 times higher than the structure with a honeycomb lattice core. The failure occurred in the form of horizontal shear failure at the core area.