Interfacial Bonding Performance Between Wood–Plastic Composite and Glass Fiber‐Reinforced Polymer in a Wetting–Drying Cycling Environment

ABSTRACT Wood–plastic composite (WPC) is a lightweight, corrosion‐resistant, environmentally friendly, and recyclable building material that is widely used in outdoor engineering projects. Glass fiber‐reinforced polymer (GFRP) sheets, which are characterized by light weight and high‐strength, can effectively improve the mechanical properties and decrease the creep of WPC when it is subjected to long‐term loading. Owing to the great differences in mechanical properties and moisture absorption between GFRP and WPC, interfacial debonding usually occurs because of alternating loading and environmental humidity. In this study, the interfacial bonding performance of GFRP–WPC was investigated. Considering the effects of the GFRP sheet thickness, bonding length, bonding width in the natural environment, and number of wetting–drying cycles, 16 groups of samples were designed, and single shear tests were carried out. The results showed that the GFRP sheet thickness significantly affected the interfacial effective bonding length, which increased by approximately 12.20% when the thickness increased from 0.6 to 1.2 mm. The interfacial ultimate bearing capacity was influenced primarily by the bonding length and GFRP sheet thickness. The interfacial bonding failure modes, strain/stress distributions, and bond–slip curves were also obtained. A theoretical model for the interfacial ultimate bearing capacity of GFRP–WPC, which included wetting–drying environmental parameters, was constructed. The calculation results were in good agreement with the experimental data.