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High tall buildings are more susceptible to dynamic excitations such as wind and seismic excitations. In this paper, design procedure and some current applications of tuned mass damper (TMD) were studied. TMD was proposed to study response of 20 storey height building to seismic excitations using time history analysis with and without the TMD. The study indicates that the response of structures such as storey displacements and shear force of columns can be dramatically reduced by using TMD groups with specific arrangement in the model. The study illustrates the group of four TMDs distributed on the plane can be effective as reinforced concrete core shear wall.

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Structural vibration control is one of the most important features in structural engineering. Real-time information about seismic resultant forces is required for deciding module of intelligent control systems. Evaluation of lateral forces during an earthquake is a complicated problem considering uncertainties of gravity loads amount and distribution and earthquake characteristics. An artificial neural network (ANN) has been trained in this article to estimate these forces. This ANN was trained on the results of time history analysis of a three-story building under 702 different loadings. Results of numerical examples verify that the trained ANN can predict the expected forces with negligible deviations.

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Considering the depletion of fossil fuel resources and their environmental impacts, offshore wind energy has emerged as a promising renewable solution. However, floating offshore wind turbines (FOWTs) are exposed to complex aerodynamic and hydrodynamic loads, particularly under combined wind and wave excitation, which can lead to excessive vibrations and fatigue damage. Therefore, effective vibration control strategies are essential to enhance structural reliability and durability. This study investigates the dynamic behavior and vibration mitigation of a floating offshore wind turbine supported by a Tension Leg Platform (TLP) under moderate, high, and extreme wind-wave conditions. A coupled model was developed using FAST-SC, and Multi-Tuned Mass Damper (MTMD) systems were implemented as passive control devices. The optimal MTMD parameters and installation layouts were determined, and their effectiveness in reducing tower and platform responses was evaluated. The results demonstrate that the optimized MTMD systems significantly improve the dynamic performance of the FOWT, achieving maximum reductions of 34% in tower fore-aft displacement, 43% in platform roll motion, and 41% in tower-base bending moment compared with the uncontrolled case. These reductions indicate the capability of MTMD systems to suppress structural vibrations, mitigate fatigue accumulation, and enhance the long-term reliability of offshore wind turbines. Consequently, the proposed approach has the potential to extend the service life of critical structural components and reduce maintenance requirements and life-cycle costs. This study provides valuable insights for the design of reliable and durable floating offshore wind turbines operating in harsh marine environments.