Analysis of Load-Bearing Capacity and Lateral-Torsional Buckling (LTB) Stability of OSB Laminated and I-Beams Made of Wood and Wood-Based Materials

The study presents experimental and numerical analyses comparing two types of wood-based structural beams—laminated beams made of oriented strand board (OSB) and traditional wooden I-beams. Load-bearing capacity, stiffness, and susceptibility to loss of stability were compared. Full-scale four-point bending tests were conducted on 5400 mm-long beams with 300 mm cross-sectional height, in accordance with the European Organisation for Technical Approvals (EOTA) guidelines. The results showed that OSB laminated beams, despite having about 20% lower bending stiffness, achieved up to 46% higher ultimate load capacity compared to I-beams. Failures in I-beams were mainly initiated by material defects and weaknesses in the glued joints of flanges, whereas laminated beams exhibited more uniform and predictable behaviour with greater repeatability of results. Numerical simulations performed in Abaqus/Standard 2022, including linear buckling and modal analyses, confirmed the experimental findings and indicated higher global stability and dynamic stiffness of laminated beams. The numerical model was validated in the elastic range and subsequently used to assess stability and dynamic behaviour, which are governed by linear elastic stiffness. The obtained results demonstrate that OSB laminated beams can serve as a potential alternative to conventional I-beams in structural applications requiring high safety and durability, offering a structurally efficient and more failure-tolerant configuration.