Multiple TMDS Coupled with Viscous Dampers to Improve Acceleration Performance and Robustness of Buildings Subject to Wind-Induced Vibrations

The performance of a novel configuration of multiple tuned mass damper (MTMD) proposed by the author for floor acceleration reduction of linear elastic buildings subjected to broad-band wind force excitation is studied. To improve efficiency and robustness under variations or uncertainties of main-structure dynamic parameters, three single degree of freedom mass dampers in parallel are tuned to different frequencies close to the natural frequency of the target mode of vibration of the main structure and the classical viscous damping elements that connect the TMDs to the main structure are replaced by dampers that connect the masses of the TMDs. This special coupling between parallel TMDs is called viscous-coupling multiple tuned mass dampers (VCMTMD). The effectiveness of the proposed technique is evaluated and compared with conventional TMD and uncoupled MTMD configurations for the same total mass of the TMDs. The reduction of root mean square acceleration and deformations of the main structural system subjected to broad-band excitation is analyzed and compared with those of a conventional optimal TMD and of a parallel MTMD without coupling. The VCMTMD outperforms both the conventional TMD and parallel MTMDs in terms of deformation and acceleration reduction of the structure with the proposed TMD viscous coupling. The VCMTMD shows high robustness to changes or uncertainties in main-structure parameters (mass or stiffness). The proposed TMD configuration can find practical applications in wind-induced acceleration reduction in high-rise buildings and vibration reduction in different structures subjected to broad-band loading.