Flexural ductile behavior of glued laminated bamboo (glubam) beams equipped with steel fuse bars

Glued laminated bamboo (glubam) is an engineered material known for its high strength and sustainability. However, its inherent susceptibility to brittle flexural failure and limited ductility raises significant concerns regarding the safety and robustness of glubam structures. This study addresses these limitations through experimental, theoretical, and numerical investigations on the flexural ductile behavior of pre-cracked thin-strip glubam beams equipped with steel fuse bars. Pre-cracks were introduced at the mid-span to promote the yielding of fuse bars at their weakened core sections before the beam’s failure. Four series of beams were tested under a four-point bending load, with and without fuse bars, varying in bar lengths and pre-crack configurations. The experimental results revealed a significant enhancement in ductility for pre-cracked beams with fuse bars, with the GB-LR1C series exhibiting a 2.5-fold improvement. However, pre-cracking led to a reduction in load-bearing capacity by approximately 45 %. These findings were validated through theoretical models and numerical simulations, which accurately predicted the initial stiffness, mid-span deflection, curvature, ductility, and flexural capacity. Parametric analyses were further conducted to emphasize the influence of fuse bar configuration and pre-crack characteristics on optimizing the flexural performance of beams, providing valuable insights into a robust structural design of glubam.