Slip modulus of inclined screw connectors in glued laminated bamboo and wood-concrete composite beams

The existing research has predominantly focused on the shear behavior of inclined screws in wood-concrete composite beams. However, there is a significant research gap regarding the slip modulus of inclined screw connectors in glued laminated bamboo and wood (GLBW)-concrete composite beam. To address this gap, nine groups of shear tests were performed to study the load-slip behavior of inclined screw connectors in GLBW-concrete composite beams. This study analyzed the impacts of screw embedding length, screw diameter, screw embedding angle, and bamboo board thickness on the slip modulus of inclined screw connectors. The results showed that in comparison to inclined screw connectors with a 90 mm embedding length, the slip modulus of screw connectors with 110 and 130 mm embedding lengths increased by 11% and 19%, respectively. As the screw embedding angle decreased, the slip modulus of inclined screw connectors increased. For bamboo thicknesses of 30, 60, and 300 mm, the slip modulus of inclined screws was improved by 40%, 78%, and 89%, respectively, compared to the screws in pure wood beam. This study presented an analytical model for predicting the slip modulus of inclined screws in GLBW-concrete composite beam based on the layering method and elastic foundation beam theory.