In-plane strength of concrete-filled steel tubular circular arches

摘要

A number of concrete-filled steel tubular (CFST) arch bridges have been constructed in recent years. In current design practice, the philosophy for the strength design of concrete arches is widely adopted for CFST arches. The CFST arches are considered under axial or eccentric compression and are treated similarly to CFST columns. The strength design method for CSFT columns is associated with the classical buckling theory of CFST columns. However, under transverse loading, the buckling behaviour of CFST arches, particularly shallow CFST arches, is very different from that of CFST columns. In addition, transverse loading produces non-uniform compressive and bending actions in CFST arches. Hence, it is doubtful if the current method for strength design of CFST columns can provide a correct strength design for CSFT arches. This paper presents a method for the in-plane strength design of CFST circular arches. Lower-bound design equations for the in-plane strength of CFST arches are proposed, and their predictions for the in-plane strength of CFST arches are compared with finite element results.