A LOW-DIMENSIONAL MODEL FOR THE FLEXURAL-TORSIONAL BUCKLING AND VIBRATION ANALYSIS OF PULTRUDED FRP ANGLE SECTION COLUMNS

Due to its efficiency, thin-walled elements with open sections have advantageous applications in engineering. In this paper, a low-dimensional model based on the classical plate theory (CPT) is proposed in order to investigate the flexural-torsional buckling behavior and vibration characteristics of monosymmetric and asymmetric angle section columns made of a pultruded fiber-reinforced polymer (FRP). First, a generalized beam software (GBTUL) is used for investigating the modal participation of different deformation modes on the linear buckling and vibration analysis. The angle section is modelled as two plates and the continuous system is discretized by using the Rayleigh’s energy method. Validation of obtained elastic critical loads and vibration frequencies is performed by means of both the GBT software and, for long profiles, a global formulation derived from Vlasov theory. A good agreement for both long and short columns has been observed, confirming the accuracy of the proposed low-dimensional model. The model is used to investigate the influence of the physical and geometrical parameters on the buckling load, fundamental frequency and the respective mode shape.