Behaviour of perforated GFRP tubes under axial compression

• Perforated GFRP tubes with multiple holes have been tested under axial compression.
• Influences of different parameters on behaviour of perforated GFRP are investigated.
• Design equations are developed to predict the capacity of perforated GFRP tubes.

This study investigates the influences of various parameters on the behaviour of perforated Glass Fibre Reinforced Polymer (GFRP) tubes under axial compression. A total of 15 GFRP tubes with and without perforations were tested under axial compression. All the GFRP tubes were divided into two groups: 12 tubes with 89 mm outer diameter and 6 mm wall thickness and 3 tubes with 183 mm outer diameter and 8 mm wall thickness. The influences of hole diameter, vertical hole spacing, tube diameter, perforation pattern, transverse hole spacing, and hole reinforcement on the axial compressive behaviour of perforated GFRP tubes were experimentally investigated. Considerable decreases in the axial stiffness, axial critical load, and axial deformation capacity of perforated GFRP tubes have been observed. The hole diameter, tube diameter, perforation pattern, and transverse hole spacing significantly influence the axial compressive behaviour of perforated GFRP tubes. However, the influences of vertical hole spacing and hole reinforcement have been observed not significant. Design-oriented equations for the prediction of the axial stiffness, axial critical load and axial deformation capacity of perforated GFRP tubes under axial compression have been proposed. The proposed equations have been found to be in good agreement with experimental results and can be used for the reliable design of perforated GFRP tubes.