Life-cycle cost analysis of steel frames with shape-memory alloy based dampers

The shape-memory alloy (SMA) based dampers are passive dampers, with their most important feature being their memory and super elastic effect. They significantly reduce the residual response displacements of the structure subjected to earthquakes. Although the initial cost of these dampers is high, they can lower the structural expected life-cycle costs subjected to earthquakes. This study dealt with the life cycle cost analysis to calculate the expected costs of the structures equipped with shape-memory alloy-based dampers. Subsequently, two 4-and 12-story steel frame structures were investigated in controlled and uncontrolled cases in terms of life cycle costs. The results revealed that these dampers can reduce the inter-story drift ratios and the residual dis-placements of the 4-story structure subjected to the design level seismic acceleration by 31% and 63%, respectively. This reduction for the 12-story structure was 39% and 83%, respectively. Also, these dampers would decrease the total life-cycle cost of the 4-story and 12-story by 53%, and 90%, respectively. Finally, the result indicated that the total life-cycle cost was reduced upon increasing the capacity of the SMA-based dampers up to a specific capacity, beyond which the dampers would not play a role in reducing total life-cycle costs.