On the Local Buckling of Pultruded GFRP I-Section Columns

Abstract

This paper aims to present the results of an experimental program on the local buckling behavior of GFRP I-section column. Characterization tests were made to determine the material properties and twenty-eight stub columns having three different flange-to-web ratios, overall lengths and end-condition were tested under compression. With the aid of the software GBTUL, based on the Generalized Beam Theory, the so-called signature curves (critical stress versus length) were obtained and lengths were determined to ensure ‘pure’ local buckling. Experimental data are reported and a discussion on the observed behavior is made, including strength, pre-buckling behavior, post-buckling reserve of strength and the influence of length and end-conditions in the critical load. It is also shown that the use of traditional Southwell plot technique leads to greater critical loads.