Seismic Performance Assessment of Semi Active Tuned Mass Damper in an MRF Steel Building Including Nonlinear Soil-Pile-Structure Interaction

Abstract

In this study the efficiency of Semi Active Tuned Mass Damper (STMD) on seismic response reduction in a moment resisting frame steel building considering soil-pile-structure interaction is investigated in comparison with common Tuned Mass Damper (TMD). Substructure method is used for simulating the Soil-Pile-Structure interaction. p-y curves recommended by API are used for simulating the nonlinear spring coefficients. Damping ratio of STMD is optimized during dynamic loading simultaneously by using Groundhook Algorithm and a layered soil profile with varying stiffness (two and three layers) is considered. In addition, the mass ratio for STMD is assessed for obtaining the highest efficiency for STMD to mitigate the seismic vibration. The results indicated that, the STMD efficiency reduces when the soil stiffness is increased. TMDs performed poorly for seismic control of structural performance in comparison with STMDs when soil pile structure interaction was ignored. Finally, the optimized mass ratio considering soil-pile-structure interaction for STMD is evaluated, which have shown that a range of 3 to 5% is suitable for efficient design of STMDs. However, it is worth noting that the seismic responses of soil-pile structure systems under near-field and far-field earthquakes do not have significantly different effects on STMD performance.