Compressive behaviour of hollow box pultruded FRP columns with continuous-wound fibres

Pultruded Fibre Reinforced Polymer (PFRP) composite profiles now have been utilized in many Civil and infrastructure applications due to their low density and outstanding mechanical properties. However, different manufacturing techniques have been used to produce these PFRP profiles, and these have an influence on the structural performance of the PFRP profiles. This study investigated the compressive behaviour of the PFRP profiles manufactured using the Winder technology, allowing continuous-wound fibres to reinforce the PFRP profiles transversely. Three different cross-sections and three levels of Length-to-Depth (L/D) ratios have been tested to study the effect of these parameters on the compressive strength of the PFRP profiles. It was observed that continuous-wound fibres led to progressive failure and prevented the splitting failure at corners. Test results showed that rectangular profiles performed structurally better than the square profiles. Moreover, the increase in L/D ratio decreased both stiffness and strength but led to higher displacement buckling capacity. It was observed that the buckling waves were governed by a polynomial function. Finally, the existing models were examined in relation to the experimental results where the general plate theory was valid to present the local buckling behaviour of the tested PFRP profiles.

Automated summary

Research on the compressive behavior of Pultruded Fibre Reinforced Polymer (PFRP) profiles reveals that continuous-wound fibers help prevent splitting failure and result in better structural performance in rectangular profiles compared to square profiles. Increasing the Length-to-Depth (L/D) ratio improves displacement buckling capacity but reduces stiffness and strength.