Simplified flexural strength calculation for rectangular concrete-filled steel tubular continuous truss girder

The concrete filled steel tubular (CFST) truss girder consists of a CFST truss and a concrete deck. The failure mechanism and flexural strength of the girder were observed to be different under various failure modes, especially for continuous girder. To promote the engineering application of this innovative type of girder bridge, a fast strength prediction method with high accuracy was proposed which can be used in preliminary design stage. The method was developed based on pin-jointed analysis and the efficient factors of truss members were defined. The failure modes prediction and flexural strength calculation can be achieved by comparing the efficient factors of different members. The prediction results of simplified method were verified by the finite element analysis. The method can take the joint resistance into consideration and greatly simplify the design process of the CFST girder bridges. The design recommendations of the CFST truss girder were proposed based on the simplified method.