Integrating soil-structure interaction uncertainties into reliability-based design optimization of TMD-equipped tall building

Tuned mass dampers (TMDs) are widely adopted for vibration control of tall engineering structures subjected to lateral loads such as earthquakes and winds. Although the design, implementation, and performance of TMD for structural vibration control have been widely investigated in the literature, determining the optimum parameters of TMD is contested. As an example, disregarding the effects of soil-structure interaction (SSI) may result in suboptimal design parameters of TMDs, especially for tall buildings. This is why soil structure parameters were recently considered for a more realistic optimum design of TMDs. Nevertheless, because of the unpredictable variations in soil's mechanical characteristics, assessing the reliability of the system necessitates addressing a probabilistic problem. In this paper, the optimum design of TMD parameters is performed in a deterministic and probabilistic framework employing metaheuristic techniques and optimization approaches based on reliability in design. The objective function of this study is the transfer function of the top story displacement. Mass, stiffness, and damping of the TMD are considered as design variables. An enhanced metaheuristic algorithm is comparatively employed to find the most efficient solution of the deterministic optimization problem. Finally, the TMD optimum parameters considering uncertainty in soil parameters are identified by a novel double-loop combination of reliability-based design optimization (RBDO) and Big-Bang Big-Crunch optimization (BB-BC). The effectiveness of the proposed procedure is assessed concerning a 40-story shear building equipped with TMD, considering soil-structure interaction. Numerical results show that the uncertainty in soil-structure interaction significantly affects the optimum design of TMD for tall buildings. The accuracy of the proposed RBDO method is validated by performance indexes under some natural ground motions.