Fatigue‐resistant Fe‐Mn‐Si‐based alloy seismic dampers to counteract long‐period ground motion

In recent years, resonance in high‐rise buildings due to long‐period ground motion, which induces large‐amplitude cyclic deformation of seismic dampers, has become a matter of significant concern. Performance requirements for seismic dampers that are installed in vibration‐controlled buildings have become more stringent, and durability against cyclic deformation has become essential. An Fe‐15Mn‐4Si‐10Cr‐8Ni alloy with enhanced low‐cycle fatigue resistance has been developed to produce steel seismic dampers that are durable against large‐amplitude cyclic deformations. We used this alloy to develop two types of fatigue‐resistant seismic dampers (shear panel and brace‐type) that counteract long‐period ground motion. Furthermore, cyclic loading tests were conducted to validate the deformation performance and fatigue resistance of the developed damper. The results indicated that these dampers exhibit significantly better fatigue life than conventional steel dampers and exhibit outstanding deformation performance and durability under low‐cycle fatigue. The proposed two types of dampers were installed on steel structure buildings in Japan. These dampers ensured that the buildings with seismic performance margins can withstand long‐period and long‐duration ground motion and repeated after‐quakes. We proposed fatigue resistant seismic dampers that are made of a Fe‐Mn‐Si‐based alloy and designed to counteract long‐period ground motion. Our results of cyclic loading tests show the designed dampers have a significantly better fatigue life than conventional steel dampers and offers outstanding deformation performance and durability under low‐cycle fatigue. Additionally, shear panel and brace‐type seismic dampers made of this alloy were installed on steel structure buildings in Japan.