Moso bamboo (Phyllostachys pubescens Mazei ex H. de Lebaie), one of the most commonly used species in China, is a strong and stiff material. In this paper, the manufacturing process for glued bamboo laminate (GBL) is presented. The mechanical properties of GBL (compression strength, bending, tension, and shearing) were tested. Results indicated that the mechanical properties of GBL were significantly different for different grades of GBL, but that the performance of GBL was controllable. The edge butt joint greatly influenced the tensile performance, but the butt joint had little impact on the bending performance. In addition, the good mechanical performance of GBL is sufficient for engineering members, making it a potentially useful bamboo product for engineering.

Bamboo is a natural bio-composite that has outstanding mechanical properties. Fibers are the structural building block of bamboo. Understanding the effect of fiber area on tensile properties of moso bamboo (Phyllostachys pubescens Mazei ex. H. Lebaie) will shed light on natural efficient design of bamboo. In this paper, fiber area and tensile properties of bamboo were tested on four bamboo slices, and a relationship found between fiber area and tensile properties. The results indicated that fiber volume increased exponentially in the radial direction from the inside to the outside of the culm wall. Bamboo tensile strength and MOE were linearly proportional to the fiber area. Fiber area also influenced bamboo fracture modes.

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The remarkable fracture toughness of bamboo culms is highly attributed to the proper embedding of the stiff fibre caps of the vascular bundles into the soft parenchyma matrix. In this study, the fracture behaviour of small specimens of moso bamboo (Phyllostachys pubescens) in tension and bending were investigated in situ with a scanning electron microscope (SEM) to visualise crack initiation and propagation within bamboo tissues and its interactions with the structural components (fibres and parenchyma tissues). Fracture surfaces were studied by field-emission SEM. The fracture of bamboo in either tension or bending was non-catastrophic, and cracks propagated in a tortuous manner with massive interfacial delamination. The stiff fibre bundles played an important role in restraining crack propagation, acting as bridges to inhibit cracks opening and also as “crack stoppers” inducing extensive crack-deflections. Microstructural analysis of the fractured surfaces revealed that substantial interfacial debonding, sliding and fibre pull-outs occurred at various length scales, which are believed to be effective in dissipating the crack energy. The synergistic effects of crack-deflection, crack-bridging and interfacial debonding are regarded to be mainly responsible for the remarkable fracture toughness of bamboo.

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Bamboo is a natural bio-composite material that is both tough and possesses excellent mechanical properties. Its delicate structure and fiber arrangements play an important role in the mechanical properties and the fracture performance of bamboo. In this study, the fracture behaviors of bamboo due to tensile strength and bending were investigated using synchrotron radiation micro-computed tomography and environmental scanning electron microscopy (ESEM). Both tension and bending tests revealed that fibers are the key factors for bearing extra load and impeding crack propagation. Crack paths were found to be different in bamboo strips with different fiber percentages, and the interface between pulled-out fiber bundles and fiber break (in helix breaks and shearing break) was observed to be typical fracture characteristics in tension. Moreover, advanced micro-matrix cracking, interface debonding, fiber bundle bridging and the splitting of cell wall layers were found to be important fracture characteristics in bending. Both in tension and bending, a reasonably weak interface appeared to be beneficial for improving fracture toughness of fiber-reinforced bamboo. Thus, it is clear that “fiber bridging” mechanisms and “shear-lag theory” are well exhibited in bamboo.

Bamboo is a natural material widely used in buildings and bridges that has good mechanical properties. However, the longitudinal connection of bamboo culms is a major problem for the bamboo industry. In this study, sleeve-nailed bamboo specimens were produced, which contained three bamboo pieces. Two bamboo pieces with similar diameters were longitudinally joined by inserting a short bamboo culm with a smaller diameter, fixed with nails. The flexural performance of single beams and two-culm beams were studied. The load-displacement curves and fracture behavior of the specimens were investigated. The results show that the flexural bearing capacity of the single connected bamboo specimen was relatively smaller than that of an unconnected one, while the flexural bearing capacity of the two-culm beam was improved significantly. It can be seen that the lateral connection of bamboo specimens can improve the bearing capacity of the combined bamboo culms. This study provides a basis for promoting the application of sleeve-type nailed connections for bamboo.