Flexural Performance of Composite Bamboo-Concrete Beams

Three bamboo-concrete composite beams and one companion bamboo beam were tested to investigate the composite efficiency and the effects of shear connectors on bamboo-concrete composite beams. The shear connectors of these composite beams consisted of dowels, notches or notch-dowels. The results indicate that the composite beams connected with dowels fail owing to the tensile fracture of the bottom-most bamboo fiber. Furthermore, the composite beams connected with notches or notch-dowels fail owing to the shear connectors. The longitudinal shear failure occurred in the bamboo along the horizontal line located at the bottom of the notches. Compared to the companion bamboo beam, the load corresponding to the displacement of the 1/250 span of the bamboo-concrete composite beam increases by 3.18 to 3.74 times and the sectional stiffness is significantly enhanced. The effective sectional stiffness of these composite beams reaches up to 70% of the sectional stiffness of the full composite beams. For the composite beams connected with notches or notch-dowels, the interfacial slip is smaller than 1.2 mm, the load-deflection relationship is linear, and the connectors exhibit the performance of a rigid connection.