Parameter Design of Graded‐Yield Dampers Based on the Starfish Optimization Algorithm

ABSTRACT

To overcome the limitation of traditional metallic dampers in adapting to uncertain earthquake intensities, this study proposes a parameter design method for a four‐stage graded‐yield metallic damper based on the starfish optimization algorithm (SFOA). The SFOA utilizes a comprehensive evaluation function based on interstory drift angle and floor acceleration as performance metrics. According to this algorithm, optimal mechanical parameters for conventional single‐yield‐point dampers under frequent, moderate, rare, and extreme earthquakes were obtained. Then, these parameters formed the basis for constructing the backbone curve and hysteretic model of a four‐stage graded‐yield damper. The nonlinear time‐history analysis results show that the vibration reduction effect of a nine‐story steel frame installed the four‐stage graded‐yield damper under different seismic intensity levels is nearly equivalent to that of every optimal single‐yield‐point damper corresponding to each seismic level. Finally, compared with the optimized single‐yield‐point damper in moderate earthquake, the proposed four‐stage graded‐yield damper can provide superior seismic response control under frequent, rare, and extreme events, respectively. This study proposes a method for determining the optimal design parameters of a four‐stage graded‐yield damper and its hysteresis model construction method, which verifies their effectiveness and has important engineering application value.