ABSTRACT
Although composite steel and concrete truss girders have been designed for many years, their behavior is not understood sufficiently yet. Decades ago an important experimental research in the field of composite trusses was performed especially in the USA and Canada by Galambos & Tide (1970), Iyengar & Zils (1973) and others. In ninetieth of the last century the comprehensive research by Skidmore et al. (1992) resulted in design recommendations showing wide range of relevant design aspects. Researches proved that plastic design (if permitted) can proceed with reasonable accuracy as for the common composite web girder. This is due to ductility of shear connection and redistribution of the longitudinal shear flow. In case of elastic design, which is needed for class 3 and 4 cross section, rigid shear connectors, in the design of fatigue and generally required for bridges the distribution of longitudinal shear flow is, however, highly nonuniform, with shear flow peaks above truss nodes.
