Design and construction of a vehicular bridge made of glass/polyester pultruded box beams V. Kostopoulos* 1,2 , Y. P. Markopoulos 1,2 , D. E. Vlachos 1,2 , D. Katerelos 2 , C. Galiotis 2 , T. Tsiknias 3 , D. Zacharopoulos 4 , D. Karalekas 5 , P. Chronis 6 and D. Kalomallos 7 The design and construction is described of a vehicle bridge made of glass-reinforced polyester pultruded box beams. The bridge has a simply supported span 11 . 6 m long and 4 m wide. It has been designed as a Class 30 (300 kN load capacity) according to DIN 1072 and represents a single traffic lane. The composite bridge consists of a 3-D truss structure made of thick-wall fibre- reinforced plastic longitudinal box elements of hollow square cross-section. The bridge design proposed allows for fast construction as it consists of pre-fabricated, ready to assemble elements. The total of the composite bridge does not exceed 135 kN. Keywords: Bridge, Truss, FRP, Pultrusion, FEM Introduction The use of low-cost composites in construction presents a major challenge to communities in both engineering and the polymer industry Although, in such applica- tions, composite materials are inferior to traditional materials such as steel-reinforced concrete in terms of ductility, they offer a number of advantages such as high specific stiffness and strength, excellent corrosion resistance and low maintenance cost, which under certain circumstances make them very attractive for application in the construction industry. These advan- tages have motivated research groups to consider fibre- reinforced plastics (FRP) as an alternative material for bridge construction. To date the following applications have been considered: 1 (i) retrofitting schemes to repair and upgrade bridge components, 2,3 (ii) design of replacement bridge components 3–5 and (iii) design and construction of new bridge structures either for pedestrians or highway applications. 1,6–10 Regarding the last category, there has been a strong drive over the last decade for the design and construc- tion of FRP pedestrian and light-traffic vehicular bridges. More recently, heavily loaded vehicular bridges have also been constructed out of FRP. In the UK, the first FRP bridge that carries trucks crosses the Stroudwater Canal 7 and has a span of 8 . 2 m and a width of 4 . 34 m. In the US, it is worth mentioning the Lockheed Martin Corporation Bridge, 6 which has a 9 . 14 m span and a load carrying capacity of 444 . 8 kN. The bridge is made of pultruded panels that form the bridge deck and are attached to three U-shaped girders with mechanical fasteners. It is now widely accepted that the most attractive industrial process for the manufacture of FRP large beam structures is pultrusion. This process imposes fewer restrictions on the designer when developing structural shapes and it can yield products of constant beam cross-section and of unlimited length provided that practical transportation considerations have been taken into account. The present work deals with the design and construc- tion of a highway bridge made of glass-reinforced polyester pultruded box beams. The final bridge construction consists of a 3-D truss superstructure made of two parallel layers formed by one-piece longitudinal box elements of hollow square cross section, which are interconnected with box elements of the same geometry. Truss members are held together by steel connection joints. The deck is formed by glass-reinforced polyester transverse beam elements of two different cross sections. Adhesive bonding and mechanical fastening have been used joints. Figure 1 shows an overall view of the structure. The top-wearing surface is formed by a 6 mm thick layer of UV resistant, flake-reinforced polyester resin. Special care has been taken for the easy assembly of the bridge, minimizing the need for experienced personnel and time. The bridge has a span 11 . 6 m long and 4 m wide and represents a single traffic lane. The bridge is Class 30 according to DIN 1072 (i.e. load bearing capacity of 300 kN) and 1 Applied Mechanics Laboratory, University of Patras, 26500 Patras, Greece 2 Institute of Chemical Engineering and High Temperature Chemical Processes, FORTH, Platani, 26500 Patras, Greece 3 T. Tsiknias & Associates, Structural Engineers S.A., Keas 67, 11255 Athens, Greece 4 Department of Civil Engineering, Democritos University of Thrace, University Campus, 67100 Xanthi, Greece 5 Dept of Industrial Management, University of Piraeus, Karaoli & Dimitriou 80, 18534 Piraeus, Greece 6 K. Chronis S.A., Tatoiou 54, 14451 Athens, Greece *Corresponding author, email kostopoulos@mech.upatras.gr 7 C.I. Sarantopoulos S.A., Streit 17-19, 15237 Athens, Greece ß 2005 Institute of Materials, Minerals and Mining Published by Maney on behalf of the Institute Received 5 February 2005; accepted 20 July 2005 DOI 10.1179/174328905X55641 Plastics, Rubbers and Composites 2005 VOL 34 NO 4 201