Lightweight carbon fibre rods and truss structures

Lightweight carbon fibre rods and truss structures are of growing importance for modern transportation technologies. The struts of such frameworks are commonly designed as fibre-wound CFRP tubes. Here CFRP sandwich rods are an advantageous alternative. They have a lightweight foam core covered by a relative thin layer of composite material. In many real applications, however, the superior mechanical properties of such struts can only be utilized with appropriate load transfer elements. Two types of load transfer elements designed for high tensile and compressive loads with a simple screw connection will be described. The framework structures discussed in this paper refer to framework beams which have, in their simple version, cross-sections of an equilateral triangle. To realise a single point support at the ends of the beam-like truss, the rail struts must converge into a conical structure. The presented structures are connection designs without any metallic elements. An outstanding application of CFRP-trusses, rod connectors, and the mentioned formlocking load transfer elements can be found in the advanced lightweight structure of a recently developed semi-rigid airship, the Zeppelin NT.