2018 Volume 25 Issue 97 Pages 97_13-97_23
Fatigue damage of bellows damper due to girder deformation caused by temperature change is examined. The bellows damper is connected between girders and abutments to reduce damage of superstructures and substructures. A design method to develop the compact and high-performance seismic dampers was proposed by the authors in which the bellows dampers are permitted to be subjected local inelastic cyclic strains due to temperature expansion and contraction of girders. In this paper, low-cycle fatigue properties of the bellows designed by the proposed design method are investigated based on P/V difference method as one of cycle-counting methods through fatigue analysis and low-cycle fatigue tests of the bellows. Fatigue strength of the bellows is examined using the equation of Manson-Coffin and the Miner's cumulative damage law. In addition, the validity of the proposed damage evaluation method for low-cycle fatigue of the bellows dampers is verified by variable amplitude loading fatigue tests of the bellows.