ABSTRACT
The study presented in this paper describes the evaluation of six full-scale GFRP composite columns. The pultruded columns had a “Universal” cross section with E-glass fibers in various forms as reinforcement and polyester as a binding matrix. The slenderness ratios (L/r) of the investigated columns were 5.69 and 33.5 corresponding to unbraced lengths of 18 in. (0.46 m) and 8 ft. (2.44 m). All columns were tested in a vertical position and under compressive axial static loading and fixed-pinned and pinned-pinned end conditions. The columns’ compressive strains, buckling and crippling loads, lateral displacements, initial curvatures, and modes of failure were documented during the course of this investigation. The orthotropic mechanical properties of the composites were experimentally obtained utilizing coupons which were cut from similar column specimens. Results from linear finite element buckling analyses conducted on full column models were compared to the behavior observed in the laboratory during the testing of specimens. In addition, the unstiffened flanges of the columns were analyzed with various boundary conditions using the classical orthotropic plate theory in order to establish the upper and lower bounds of the members’ local flange and web buckling capacities. Based on experimental evaluations and analytical analyses’ results, conclusions were drawn and design recommendations were made.
