On the pin-bearing failure load of GFRP bolted laminates: An experimental analysis on the influence of bolt diameter

This paper presents results summary of an experimental investigation aimed at evaluating the influence of the bolt diameter on the bearing failure strength of glass fibre reinforced polymer (GFRP) bolted laminates with epoxy matrix, for different values of fibre-to-load inclination angle. In this study, three different types of laminates were tested: one of them is mono-directional while the other two are bi-directional, with two different stacking sequence. Reductions in the pin-bearing ultimate load was found to be linearly dependent on bolt diameter. A pin-bearing design formula is also proposed based on experimental results.