English：

To explore the seismic performance of viaduct piers in high intensity mountain airport areas,an irregular three-column bracing system was designed and manufactured. Quasi-static tests wereconducted to investigate the failure mode and seismic performance of the irregular three-column bracingsystem under horizontal low-cycle reciprocal loading. A numerical analysis model considering thebending-shear coupling effect was established and compared with the experimental results to validate theaccuracy and effectiveness of the numerical analysis model. The research findings indicate that theunreasonable stress distribution in the structure leads to shear failure and loss of bearing capacity in shortpiers, while the seismic performance of long piers is not fully utilized. Based on this, comparisons weremade regarding the bearing capacity, ductility, and energy dissipation coefficient of the steel pipeconcrete short pier bracing system. It was found that the bearing capacity and ductility of the steel pipeconcrete short pier bracing system increased by 43.23% and 64.27%, respectively, and its energydissipation capability far exceeded that of the reinforced concrete short pier bracing system, demonstratingsuperior seismic performance.