Experimental study of hybrid pine-birch glued-laminated timber beams assisted by digital image correlation technique

This paper presents an experimental study on the flexural behavior of hybrid Pine-Birch Glued-Laminated Timber (GLT) beams. The study focuses on the performance of GLT beams with different lengths (2.1 and 2.8 m) and different compositions of birch (30 and 50%) and pine lamellas. The experiments were conducted using a four-point bending test and data were analyzed using Linear Voltage Displacement Transducers and Digital Image Correlation techniques. The results highlight that pure pine GLT beams exhibited brittle failure, while pure birch beams displayed a more ductile behavior. The hybrid GLT beams demonstrated a transitional behavior between the two. The presence of birch lamellas in the hybrid beams highlights the potential of these beams in structural applications, and significantly improves the global bending modulus of elasticity, bending strength, and flexural ductility compared to pure pine beams.