Shear behaviour of I-shaped steel with bamboo scrimber composite beams

Bamboo scrimber beams are prone to brittle failure, and I-shaped steel beams are prone to buckling and out-of-plane instability. To address these issues, the failure process, failure mechanism, deformation and bearing capacity of composite beams made by combining I-shaped steel and bamboo scrimber plates with structural adhesive are studied, taking the shear span ratio (lambda) as a variable. The failure modes of the composite beam are mainly bottom-up layer-by-layer tearing of the bamboo scrimber and slight out-of-plane deformation of the I-shaped steel in the late loading period. Meanwhile, the ultimate bearing capacity, load-displacement curve, load-strain relationship and strain distribution of the mid-span section of the composite beams are obtained, indicating that the overall working performance of these beams is excellent and that the comprehensive effect of the components is remarkable. The shear capacity of the composite beam increases with decreasing shear span ratio. By referring to the existing calculation formula of the shear capacity and fitting the test results, we obtain a calculation model of the shear capacity of a composite beam. The average error between the theoretical values and the test values is 11%, indicating that the method can predict the shear capacity well.