Seismic performance investigation of building structures equipped with MTMDs considering soil-structure interaction

Abstract

The traditional tuned mass damper (TMD) design criterion is obtained with the fixed base model, which is suitable for the case without significant soil-structure interaction (SSI) effects. However, when the SSI effects are notable, the TMD designed based on the fixed base model will degrade its performance and even magnify the seismic response of the main structure. Since accurately evaluating the effects of SSI on the natural frequencies of the main structure is difficult due to soil nonlinearity, single tuned mass dampers (STMDs) may easily undergo tuning failure due to frequency-limited control bandwidths. Applying multiple tuned mass dampers (MTMDs) to attenuate the vibration of the main structure may be a promising solution. In this paper, the seismic performance of a 10-story steel structure equipped with MTMDs considering SSI is investigated. A three-dimensional refined finite element model is first built. Then, a comprehensive analysis is presented by considering the different MTMDs design parameters and earthquakes. The research results show that when the SSI effect is significant, the MTMDs in reducing the seismic response of the structure have better effectiveness than the STMDs. With other MTMDs design parameters determined, the MTMDs performance is strengthened by increasing the mass ratio and the number of TMDs. The central frequency ratio is taken as the optimum frequency ratio. The bandwidth is limited to the region formed by 0.9–1.1 times the TMD optimal design frequency. The performance of the MTMDs is less influenced by the different TMD installation positions. Moreover, the MTMDs still have good robustness when considering the SSI effect.