2019 Volume 26 Issue 103 Pages 103_31-103_43
Seismic bellows dampers, which are connected between girder and abutment, are subjected to girder bending rotations due to live load. Since their occurrence frequencies are very high even though stresses due to live load are small, high-cycle fatigue properties of dampers must be examined. Fatigue properties of bellows dampers are evaluated based on high cycle fatigue tests and finite-element analyses (FEA). Firstly, bending rotation angles of girder end parts are calculated using fatigue-load (F-load), which is used for fatigue evaluation of road bridge design. Using the obtained rotation angles, stresses of bellows dampers are calculated by three-dimensional FEA models. Fatigue strength of bellows dampers is examined by high-cycle fatigue tests of bellows damper specimens. Fatigue strength of bellows dampers for live load is evaluated by test results and calculation results based on fatigue design of road bridge specification.