Designing optimal multiple tuned mass dampers using genetic algorithms (GAs) for mitigating the seismic response of structures

Abstract

In this paper an effective method has been proposed for designing optimal multiple tuned mass dampers (MTMDs) to mitigate the seismic response of structures based on defining an optimization problem which considers the parameters of tuned mass dampers (TMDs) as variables and minimization of maximum structural response as an objective function while a number of constraints have been applied on TMDs response and parameters. The genetic algorithm (GA) has been used successfully for solving the optimization problem. For illustration, for a ten-story linear shear frame subjected to a filtered white noise excitation optimal MTMDs have been designed. The results have shown the simplicity and convergence behavior of the method. It has also been concluded that the performance of MTMDs depends on TMDs mass ratio, TMDs configuration and design criteria where increasing the TMDs mass ratio has improved monotonously the performance of MTMDs especially for the domain of smaller values of the mass ratio, while for this case study the number of TMDs has not been more effective. Testing the optimal MTMDs under near-field and far-field earthquakes shows that the performance of MTMDs has been influenced by input excitation. The capability of the method in considering the effect of higher modes has been shown.

Using Optimal Multiple Tuned Liquid Column Dampers for Mitigating the Seismic Response of Structures

“…In this paper following the method proposed by Mohebbi et al [18] for optimal design of multiple tuned mass dampers (MTMDs) for MDOF structures subjected to earthquake excitation, an effective method has been proposed for optimal design of MTLCDs on multidegree-of-freedom linear structures subjected to any desired excitation. In this method, for designing MTLCDs system, an optimization problem has been defined where the minimization of the maximum structure displacement (x max ) is considered as objective and the parameters of TLCDs such as mass, total length, and head loss as variables.…”

“…In most of the previous researches on designing MTLCDs the design procedure has some simplifier assumption on TLCDs parameters. In this paper, following the method proposed by Mohebbi et al [18] for optimal design of multiple tuned mass dampers (MTMDs) on multidegree of freedom (MDOF) structures, an effective method based on optimization procedure has been used for designing optimal MTLCDs.…”

Optimal Design of Multiple Tuned Liquid Column Dampers for Seismic Vibration Control of MDOF Structures

“…These constraints on distribution of T LCD parameters for simplifying the design procedure, along with tuning the frequency of T LCDs to a specified frequency of structural mode or the need for extensive numerical analysis have been some of the drawbacks of previous design procedures used for designing MT LCDs for multi degree of freedom (MDOF) structures. Recently Mohebbi et al [23][24][25][26] have combined structural control strategies and optimization techniques to come up with efficient approaches to design different control systems. These approaches are simple and computationally efficient, and are previously used to design MTMDs [23], MR dampers [24] for linear structures as well as MTMDs [25], and active mass damper (AMD) [26] for nonlinear structures.…”

“…Recently Mohebbi et al [23][24][25][26] have combined structural control strategies and optimization techniques to come up with efficient approaches to design different control systems. These approaches are simple and computationally efficient, and are previously used to design MTMDs [23], MR dampers [24] for linear structures as well as MTMDs [25], and active mass damper (AMD) [26] for nonlinear structures. In this paper, a new approach based on using intelligent optimization techniques is suggested for optimal design of MT LCDs to overcome limitations of the previous MT LCD design methods.…”

“…In this paper, a new approach based on using intelligent optimization techniques is suggested for optimal design of MT LCDs to overcome limitations of the previous MT LCD design methods. In the proposed method which is an adaptation of a recently proposed method by Mohebbi et al [23] to design optimal MTMDs for MDOF linear structures, an optimization problem is formulated and solved to find the optimal parameters of T LCDs. The optimal parameters of each T LCD unit are determined and the MT LCDs control system is designed to minimize certain response of the structure and pursue different design objectives while satisfying some practical considerations regarding T LCD parameters.…”