Cyclic Response of Bolted and Hybrid Pultruded FRP Beam-Column Joints between I-Shaped Sections

Abstract

This paper presents cyclic behaviour of bolted and hybrid–combined bolted and bonded fibre reinforced polymer (FRP) beam-to-column joints between I-shaped members using steel and FRP cleats. Five full-scale cyclic tests are carried out to study moment-rotation behaviour, cyclic response, and failure patterns. The test parameters include position of cleat (flange or combined web and flange), fastening method (bolting or hybrid–combining bolting and bonding) and cleat material (steel or FRP). First two tests had bolted and hybrid joints with steel flange and web double angles. Next two tests had the same joint detailing but with no web cleats. Last test used bolted joint only with FRP web and flange cleats. Three failure modes were observed: shear-out failure of the beam’s bolted zone, adhesive debonding with shear-out failure and delamination cracking. Cyclic performance of the joints was assessed by hysteresis moment-rotation curves and accumulated dissipated energy. Hybrid joints showed the best overall cyclic performance with accumulated dissipated energy about 75% higher than the bolted joints. Bolted joints with FRP cleats exhibited the worst cyclic performance. Flange cleated joints showed similar performance to web and flange cleated joints.

A Review of Fibre Reinforced Polymer Structures

“…The standard profiles are produced as I, H, C, leg-angle and tubular sections, see Figure 2a. FRP elements have been used in building systems, bridges, cooling towers, chemical and food processing plants, railway platforms and marine structures [7,8,[27][28][29][30]. The first mobile five-storey FRP building Eyecatcher (Figure 2b) was exhibited in 1999 at Swiss Building Fair.…”

“…The challenge lies in dealing with the connections and joints for FRP members. FRP joint details are currently copied from steel design practice, which mostly leads to oversized FRP compo- Lightweight, high strength, corrosion resistance and expected durability over their lifetime are the key benefits of FRPs [6][7][8]. Glass or carbon fibre reinforced polymer (GFRP or CFRP) shapes are used in structural applications.…”

A Review of Fibre Reinforced Polymer Bridges

“…The fibres provide strength to the FRP part. The resin matrix provides shape, protects fibres and transfers force [1][2][3]13,76,77].…”

Fibre-Reinforced Polymer (FRP) in Civil Engineering

“…Some common sections include wideflanged sections, I-sections, parallel flange channels, rectangular hollow sections, and square hollow sections. FRP shapes have been used in chemical and food processing plants, cooling towers, lightweight foot and road bridges, building systems, railway platforms, marine structures and structures where electromagnetic transparency is needed [36][37][38][39][40][41][42]. Chemical inertness, corrosion resistance, lightweight and low maintenance are the key drivers behind the use of FRP structural components.…”