Structural behavior of steel dowel-reinforced cross-laminated bamboo and timber beams

Cross-laminated bamboo and timber (CLBT) products exemplify the efficient utilization of bamboo and timber resources, demonstrating excellent potential in sustainable structural engineering. The significant difference in mechanical properties between high-density engineered bamboo and low-density timber laminations leads to premature in-plane delamination failure and loss of ductility and energy absorption for CLBT members subjected to out-of-plane loading. This study demonstrated that vertically-driven steel dowels significantly enhanced the layer combination efficiency and addressed the above problems of CLBT. A comparison of measured critical mechanical performance parameters was presented, systematically characterizing the structural behavior of CLBT beams with steel dowels. Steel dowels in CLBT were more effective than those in cross-laminated timber at resisting high in-plane shear stress and exhibiting the progressive failure phenomenon. Although steel dowels slightly reduced the bending stiffness in some specimens, they increased the ductility and energy absorption performance, particularly in CLBT. This study provides a potential solution for improving the structural behavior of CLBT members subjected to out-of-plane loads under high in-plane shear stress conditions.