Fuzzy-entropy based robust optimization criteria for tuned mass dampers

Abstract

Tuned mass dampers (TMD) are well known as one of the most widely adopted devices in vibration control passive strategies. In the past few decades, many methods have been developed to fi nd the optimal parameters of a TMD installed on a structure and subjected to a random base excitation process, but most of them are usually based on an implicit assumption that all of the structural parameters are deterministic. However, in many real cases this simplifi cation is unacceptable, so robust optimal design criteria becomes a viable alternative to better support engineers in the design process. In Robust Design Optimization (RDO) approaches, indeed the solution must be able to not only minimize the performance but also to limit its variation induced by uncertainty. Most of the currently available RDO methods are based on a probabilistic description of the model uncertainty, even if in many cases they are not able to explicitly include the infl uence of all the possible sources of uncertainties. Therefore, in this study, a fuzzy version of the robust TMD design optimization problem is proposed. The consistency of the fuzzy approach is studied with respect to the available non-probabilistic formulations reported in the literature and an application to an example of a robust design of a linear TMD subjected to base random vibrations in the presence of fuzzy uncertainties. The results show that the proposed fuzzy-based approach is able to give a set of optimal solutions both in terms of structural effi ciency and sensitivity to mechanical and environmental uncertainties.

Robust optimization of base isolation devices under uncertain parameters

“…The main goal of the optimum design of mechanical systems with random parameters subjected to random dynamic loads is to minimize the mean value of the objective function. The optimum solutions obtained in this way are more stable with respect to those achieved by conventional deterministic approaches, which only minimize the deterministic OF and neglect the involved uncertainties (Marano et al, 2008).…”

New approaches in reliability based optimization of tuned mass damper in presence of uncertain bounded parameters

“…For single-TMD device, as it happens in the present work, a robust optimization of the TMD parameters requires the knowledge of uncertainties model [35,36], which is in out of the scope of the present work; indeed, the proposed methods (i.e. CONLM and MBEM) assume that the only knowledge of uncertain parameters is a finite box (hyper rectangle) where they lie, and that its endpoints are the only available information.…”

“…The effectiveness and robustness [30][31][32][33][34][35][36] of the proposed optimum bounds of the TMD parameters are also addressed and a performance index, using the frequency response function (FRF), is introduced. Although, robust optimum TMD parameters require further information on uncertainties, it is always necessary, for real life situations, to make a particular choice among the obtained optimum TMD parameters.…”

Effects of soil-structure interaction in seismic analysis of buildings with multiple pressurized tuned liquid column dampers

“…Equation (46) establishes a mass coupling between the structure and the passive device. For the TMD the use of the equivalent parameters is straightforward, once the optimal parameters of the attenuator are determined, either computationally as Marano et al (2010) or from classic solutions proposed by Hartog (1956), Warbuton (1981) and Warbuton (1982). Equivalent parameters of the TLD are discussed by Banerji et al (2000), Souza (2003), Bigdeli and Kim (2016), and Tait (2008).…”