Connection of profiled decking with roof purlins using high-strength bolts

Abstract

Introduction. One of the key challenges in integrating profiled decking with roof purlins and truss systems is creating a reliable, stiff connection between them. Conventional fasteners used in practice often exhibit insufficient strength around the hole edges, limiting the decking’s contribution to the overall load-bearing system. Therefore, it is important to develop design solutions that enhance the load capacity and rigidity of the joints that attach thin-walled elements to roof purlins.

Materials and methods. This study proposes and analyzes a bolted connection reinforced with carbon-fibre composite elements. A theoretical calculation of contact stresses in the washer area was carried out, conditions leading to sheet crushing were identified, and the effectiveness of the external reinforcement was assessed. Experimentally, bolted connections in H153 profiled decking (08ps steel, 1.5 mm thick) with M12 bolts were tested both without reinforcement and with overlays of epoxy-impregnated carbon fabric.

Results. Theoretically, reinforcement with carbon fibre was shown to reduce contact stresses in the connection by increasing the equivalent stiffness of the bolted joint zone. Experimentally, the reinforced connections demonstrated up to a 40 % increase in load capacity within the elastic range compared to non-reinforced joints.

Conclusions. Applying external carbon-fibre reinforcement significantly improves the reliability and stiffness of bolted connections in thin-walled profiled decking. The proposed solution ensures the joint can withstand operational loads, prevents the onset of local failures, and enables the decking to act compositely with the roof’s primary load-bearing elements.