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• Optimization of the distribution of mass is considered instead of mass ratio. • The proposed configuration of TMD is coherent, and the concentrated masses completely move in the opposite direction. • A new designing procedure of configuration of TMD was developed according to the definition of shape variables, guarantying two main aims, lighter mass and optimal distribution of mass around the torsion axis. • Proposed TMD, in addition to raising the efficiency of passive control strategy, provides a lighter mass block in comparison to other available configurations. • Suggested TMD can enhance the performance up to 2.5% compared with other existing configurations (with equal mass, damping, and frequency ratios). • The optimum situation of the proposed TMD decreases the mass ratio up to 0.2% with the same performance compared to other ones. • Proposed TMD, as a passive control system, is a reliable control system for controlling the flutter such that three suggested TMDs, placed at the middle point of each span, increase the flutter velocity up to 55% compared with the uncontrolled condition. In suspension bridges, flutter is the primary source of instability, commonly controlled by a tuned mass damper (TMD). In torsional motions, such as flutter, the shape of the mass block, indicating its distribution around the torsion axis, is critical; indeed, an optimal distribution results in a more effective and lighter device. The flutter analysis of the Vincent Thomas suspension bridge was performed using the multi-mode method in this article. Then, a new optimal configuration was used to avoid it; in addition to common parameters such as mass ratio, damping ratio, and frequency ratio, a set of parameters called shape variables was also considered. These parameters take into account the manner in which mass is distributed around the torsion axis. The performance of the aforementioned configuration was compared to that of the other recommended TMD configurations. Additionally, a general formulation of TMD was represented, which included the other configurations. Finally, the effectiveness of TMD was evaluated in comparison to other control systems. The results indicated that the optimal configuration was reliable and that it reduced the mass ratio by up to 0.2 percent by optimizing its distribution around the torsion axis compared to other existing configurations. [ABSTRACT FROM AUTHOR]

• Optimization and Interpretation of Fuzzy Controller Parameters. • The controller is installed on the roof of a 15-story building, and its characteristics are determined by a 3-dimensional (3d) finite element model of a real structure. • Investigating the performance of the suggested method by the aim of energy consumption. • FLC parameters, including fuzzy rules, shape of membership functions (MFs) and MF limitations, as well as ATMD parameters such as mass, damping, stiffness and maximum control force, were optimized subjected to both peak displacement of the last story and highest inter-story drift objective functions (OFs). • A general-purpose center of mass optimization (CMO) algorithm is established to tackle the optimization problem. All fuzzy logic controller specifications and active tuned mass damper (ATMD) parameters are simultaneously optimized under seven pulse-type near-fault earthquake records. The last story's peak displacement and the maximum inter-story drift are separate objective functions. The controller is installed on the roof of a 15-story building, and its characteristics are determined by a 3-dimensional finite element model of a real structure. Adopting a simple model, soil-structure interaction effects are investigated. Geotechnical tests of the site soil are used to determine soil characteristics. A general-purpose center of mass optimization algorithm is established to tackle the optimization problem. The algorithm results are compared with those of two popular optimization algorithms. An ensemble of twenty-four pulse-type ground motions is utilized to evaluate and validate the proposed controller. Optimal results are compared and discussed for the two objective functions, where interpreting numerical results may contain practical information about excitations and the structure. [ABSTRACT FROM AUTHOR]