Abstract
A damper system with Kogome truss structure which is known to have higher resistance to plastic buckling and lower anisotropy than other truss periodic cellular metal is introduced and its mechanical properties are covered through theoretical analysis and experimental tests. The effects of design variables such as the thickness of wire, geometric shape of the damper on the shear strength, Young's modulus is theoretically estimated and verified experimentally. By integrating the experimental results, analytic models of damper are provided. In addition, hysteresis loop of the damper under cyclic shear loading is experimentally performed to investigate the energy dissipation capacity and the performance deterioration by the fatigue. Using the hysteresis properties from the experimental tests, the mathematical models of Kagome damper can be predicted from analytical Kagome truss structure ideally assumed to be hinged connected and with no curvature of wire. In order to verify the effectiveness and applicability of the mathematical models, numerical analysis was performed for the 5-story pilotis-structure. From the numerical study, it is found that the mathematical model with smaller yielding strain has an enough energy dissipation effect to reduce the displacement and base shear force of the structure. It is also shown that the mathematical model modified with Young' modulus ratio, yielding stress ratio from theoretic model can be used to predict the hysteresis loop of Kogome damper and the improvement of seismic performance.
