Performance of Pultruded FRP Connections under Static and Dynamic Loads

Abstract

The objective of this paper is to introduce a new design concept for con necting structural pultruded shapes. In this study, evaluation of the performance of a new class of pultruded fiber reinforced plastic (PFRP) beam-to-column connections under both static and dynamic loading conditions is presented. The connecting elements are com posed of newly developed FRP universal connectors (UC), PFRP threaded rods and nuts with and without high-strength epoxy adhesives. Experimental and analytical studies on the rotational stiffness and the ultimate flexural strength are presented. A simple linearized expression for each connection is given along with the corresponding flexural ultimate capacity. Average flexural stiffness coefficients, for design purpose, are also provided. Discussion on the different ultimate modes of failure is also provided. For the dynamic part of this study, results of experimental dynamic tests of PFRP structural shapes and connections is presented. The thin-walled elements used in this study were standard "off- the-shelf" pultruded 4 " × 4 " × 1/4 " H-beam and 2 " × 2 " × 1/2 " square tube. The test specimens were excited dynamically using both impact loading and shaking loads. Ex perimental modal analysis was used to extract the natural frequencies, modal damping, and mode shapes of the test specimens.