Resistance and thermal insulation of a composite FRP–steel beam

For an optimal design of roof-elements for long spans one has to consider both load-carrying capacity and heat conductivity. In this paper three different alternative web configurations for joining web to flange in a roof-element are investigated. A composite web in combination with fibre reinforced plastics (FRP) is proposed as a solution to achieve an optimised performance. The connection is designed as a mechanical pin-type fastener with a general purpose polyester matrix FRP. Full-scale beam tests and small-scale properties test were carried out. Where connection failure took place, the derived connection capacity load matches fairly. A predicted span length of a roof element is in the order of 8–10 m in a design situation should be possible using the FRP–steel web. The load-carrying and thermal insulation performance of FRP–steel, expanded metal and slotted steel beams are compared by finite element analysis.