Incremental dynamic analyses of steel moment resisting frames with superelastic viscous dampers

Abstract

This study aims to evaluate the seismic performance of steel moment resisting frames upgraded with shape memory alloy (SMA)-based self-centering viscous dampers. The superelastic viscous damper (SVD) relies on SMA cables for re-centering capability and employs viscoelastic (VE) damper that consists of two layers of a high damped (HD) blended butyl elastomer compound to augment its energy dissipation capacity. First, the design and mechanical behavior of SVDs are described. A nine-story steel frame building is selected for the numerical analyses. The building is analyzed as (1) a conventional special moment resisting frame (SMRF), (2) a dual SMRF-buckling restrained brace (BRB) system, and (3) a SMRF with SVDs. A model of the steel building for each configuration is developed to determine the dynamic response of the structure. The incremental dynamic analysis is used to evaluate the behavior of each building under seven ground-motion records. The analytical results indicate that the SVDs improve the response of steel frame buildings under different level of seismic hazards.