An experimental study of the behavior of connections for pultruded GFRP I-beams and rectangular tubes

This paper presents the results of an experimental investigation comparing beam-to-column connection behavior of pultruded glass fiber reinforced plastic (GFRP) I-beams and box sections. We also present a novel method for measuring connection stiffness that provides new insights into the behavior of flexible connections. The tests comprised six specimens: three I-beams connections and three box-beam connections. The connections had top and bottom seated angles with web clips for the I-beams and side plates for the box beams. Two of the specimens were bolted through the column. Duplicate tests of the standard I-beam and box-beam connections were done to establish repeatability of the tests. The box beam connections performed much better than the I-beam connections with respect to both strength and stiffness. Stiffness was improved by 25% and strength increased by 280% by using the box sections with a relatively simple connection geometry.