Seismic performance and collapse prevention of concrete-filled thin-walled steel tubular arches

• We investigated the seismic behaviour of concrete-filled steel tubular (CFST) arches.
• We obtained the failure mechanism and failure modes of CFST arches under strong ground motions.
• A CFST arch undergoes global dynamic instability when subjected to a ground motion scaled to increasing intensity levels.
• A lower bound equation is proposed for the prediction of dynamic strength of CFST arches.

The primary objective of this paper is to investigate the seismic behaviour of concrete-filled steel tubular (CFST) arches using incremental dynamic analysis (IDA). A nonlinear elastic–plastic finite element model is developed using OpenSees software and is verified with a shaking table test. Single-record IDA studies indicate that a CFST arch undergoes global dynamic instability when subjected to ground motions of increasing intensity levels. During this process, either dynamic elastic buckling or dynamic elastic–plastic buckling may occur. Dynamic strength, which is defined as the capacity for preventing global dynamic instabilities of CFST arches, is determined with a series of multi-record IDA calculations. A lower bound equation that takes into account the effect of slenderness ratio, axial compression ratio, and included angle is proposed for the prediction of the dynamic strength of CFST arches.