BUCKLING STRENGTH OF GFRP EQUAL-LEG ANGLE STRUCTURAL MEMBERS UNDER CONCENTRIC AXIAL COMPRESSION

Abstract

This paper presents the results of a study on the buckling strength of glass fiber-reinforced plastic (GFRP) equal-leg angle structural members subjected to the concentric axial compression. The angle members were made of glass fiber reinforced with polyester resin and manufactured by a pultrusion process. A total of 32 specimens with slenderness ratios ranging from 12 to 187 and leg width-to-thickness ratios of 8, 12, and 16 were tested. The experimentally obtained buckling loads were also predicted by using analytical formulas. The analytical formulas were developed by modifying a well-known elastic flexural-torsional buckling theory with some factors concerning the orthotropic behaviors of the GFRP material. Coupons cut from the angle specimens were tested using compression and in plane shear coupon test to determine necessary material properties. The analytical results were then correlated to the test results and those calculated by the nominal buckling strength equations proposed by Zureick and Steffen to validate the adequacy. Finally, the design equations for the angle members were proposed