Local buckling strength of pultruded FRP I-section with various mechanical properties compression members

Design of pultruded structural shapes is often governed by the local buckling because the pultruded structural shapes have low stiffness and also cross-section of structural shapes is composed of plate components such as flange and web. Therefore, it is necessary to investigate the effects of material properties variations in the cross-section for the local buckling strength because the mechanical properties of the material are also a function of the local buckling strength. In this paper, closed-form local buckling analysis is conducted on the pultruded Fiber Reinforced Polymer plastic (FRP) I-section structural members under compression. In the analysis, mechanical property variations in the cross-section are also taken into account. It is also discussed that how the variations of material properties in the cross-section affect the local buckling strength of pultruded FRP I-section structural member. The published experimental results are used to validate the analytical results investigated in this study. From the result of investigation, it was found that even though there are significant variations in the material properties in the cross-section of pultruded FRP I-section members such material properties variations in the cross-section do not affect so much compared with the geometrical variables, such as width-thickness ratio, in the local buckling strength of the member.