Analysis of a tuned liquid column damper in non-linear structures subjected to seismic excitations

Abstract

The behavior of the tuned liquid column damper (TLCD) is analyzed in the control of non-linear structures subjected to random seismic excitations. The structure is modeled as a system of one degree of freedom with incursion in the non-linear range. The Bouc-Wen hysteretic model is used to model the non-linear behavior of the structure. A stationary stochastic analysis is performed in the domain of the frequency. An equivalent statistical linearization was used for the analysis of the main system and the TLCD. The TLCD parameters considered for the optimization process were the frequency and the head loss coefficient. Two target functions were considered, (i) reduction of the main displacement of the system, (ii) reduction of the hysteretic energy. Two random processes were considered as seismic excitation, first a broad bandwidth process and secondly a narrow bandwidth process. The results show that for a broad bandwidth process, the TLCD tends to tune with the linear equivalent frequency of the system in the case without TLCD, while for the narrow bandwidth process, it tunes (TLCD) with the dominant frequency of the input. It is seen that the TLCD becomes detuned with regard to the frequency of the structure as the structure becomes more non-linear. It is also seen that the optimal tuning ratio of the TLCD is unsensitive to the mass ratio of the device and the main damping ratio of the system. It is also concluded that in case of flexible structures, the optimal head loss coefficient tends to be lower and increases with regard to its length ratio. It is seen that the effectiveness of the TLCD is greater for higher mass ratios of the device. In addition, it is found that the optimal TLCD becomes less effective as the structure enters the non-linear range, showing lower efficiency than what is seen in the literature for optimal TLCDs in linear structures.

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

“…The results presented by Souza (2003) point out that the performance of the TLCD is comparable to the other types of liquid attenuators, but with the advantage of using a smaller amount of mass, with more stable behavior, shorter reaction time, and greater flexibility of sizing. Additionaly, Ghosh and Basu (2004); Chakraborty et al (2012) and Espinoza et al (2018) verify the efficiency of the TLCD in the control of seismic excitations. The tuned liquid column damper can also ensure operational safety and increase the fatigue life of the structures to which they are coupled as Shahrabi and Bargi (2019) demonstrate through an analytical and numerical study.…”

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Análisis de la eficiencia de un amortiguador combinado sintonizado con incertidumbre en los parámetros sometido a una excitación sísmica de alto contenido de frecuencias

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