Innovative all composite multi-pultrusion truss systems: FE modelling and behavioural issues

Abstract

Trusses are successful structural forms that have been utilised, at extended scale, since the nineteenth century. Fibre composite materials are relatively new to civil engineering applications. The increased interest in using composites in civil applications can be attributed to advantages when compared to other construction materials that offset their higher costs. Using conventional approaches for truss systems in composite materials can undermine their efficiency. This is mainly due to the stress concentration at connections which usually governs the truss design. The all-composite multi-pultrusion truss (MPT) concept was developed in the Centre of Excellence of Engineered Fibre Composites; University of Southern Queensland, Australia. It combines the usage of pultrusions for the chord and vertical members with diaphragm-type bracing. Preliminary tests of few truss alternatives show good structural performance which includes high load carrying capacity, semi-ductile behaviour and ease of manufacturing. This paper presents the main behavioural issues of this innovative structural form based on the test results and the FE analysis that well predicted the buckling behaviour of the web.