Modelling Hollow Pultruded FRP Profiles under Axial Compression: Local Buckling and Progressive Failure

Abstract Pultruded Fibre-Reinforced Polymer (PFRP) profiles are widely used as structural elements in many civil infrastructure applications. However, the anisotropic elasticity and the application-driven slenderness make these profiles prone to local buckling failure, well below their ultimate load capacity. In this paper, a numerical study was undertaken to characterise the local buckling and compressive failure of hollow PFRP profiles under axial compression. The Newton method were used along with the adaptive automatic stabilisation scheme and a controlled increment size in Abaqus 2019, to overcome the numerical difficulties in simulating local buckling. The numerical predictions were validated by experiments. The energy parameters and the constituent failure modes of the FEM models were used to explain the effect of dimension, layup, and slenderness ratio on the post-peak behaviour and failure modes of the PFRP profiles. Moreover, the reliance of the strain energy restoration after buckling and the axial and transverse deformations on these parameters was explained.