Bonded butt joints in pultruded GRP panels—an experimental study

The strength of bonded butt joints in pultruded material is investigated experimentally. The joints are bonded with commercially available two-part, cold curing, epoxy and acrylic adhesives. The aim of this work is to investigate the comparative strength of the butt joints when adhesives of differing stiffness are used to join a variety of pultruded materials. The effect of joint configuration, including a novel finger joint configuration, and mechanical surface preparation are also explored. The bonded specimens were tested to failure under static longitudinal tensile loading at room temperature. The results indicate that the quality and content of the pultruded material is an important factor in joint efficiency. The novel finger-joint configuration provides some interesting results when compared to the standard double butt-strap joints.