Yazarlar
- Araz, Onur(3)
- Kahya, Volkan(2)
- Elias, Said(1)
Yayınlar
- MakaleAçık Erişim2024Performance of differently arranged double-tuned mass dampers for structural seismic response control including soil-structure interaction
Araz, Onur; Elias, Said
Reducing vibrations occurring in structures under environmental loads makes a significant contribution to the development of structural safety. Tuned mass dampers (TMD) are one of the systems commonly used to control structural vibrations. Since TMD is adjusted according to the dominant frequency of the structure, factors that may cause changes in the frequency of the structure can significantly reduce the effectiveness of TMD. One of the main factors that can cause changes in the frequency values of the structure is the interaction between the structure and the soil. To overcome this situation, it is recommended to apply control systems consisting of multiple TMDs (MTMD) to the main structure instead of a single TMD. MTMD systems are arranged in two different types, serial and parallel. In this paper, a methodology that considers the structure-soil interaction (SSI) is presented for the optimum design of control systems with different configurations placed on a main structure under the influence of ground motion. To research the SSI effects, the TMDs-structure coupled system is supported by rocking and swaying springs and the corresponding dashpots, and then the equations of motions of the structural system are derived. In the optimization process based on particle swarm optimization in the frequency domain, different soil types, configuration types, and mass ratios are considered. The efficiency of optimum TMDs arranged in series and parallel is also evaluated using near and far fault ground motions in the time domain. Numerical results show that if structures are constructed on soils with low shear wave velocities, ignoring SSI can significantly change the design parameters and effectiveness of the control system.
- MakaleYalnız künye2019A SEQUENTIAL APPROACH BASED DESIGN OF MULTIPLE TUNED MASS DAMPERS UNDER HARMONIC EXCITATION
Kahya, Volkan; Araz, Onur
This study evaluates the response reduction effect of single-degree-of-freedom (SDOF) primary systems with multiple tuned mass dampers (MTMDs) under harmonic excitation. To design MTMD, TMD properties are re-calibrated based on the natural frequencies of the system on which the number of TMDs is one less than the current system. This is a sequential approach that does not require any iteration for each step. Instead it requires starting from the case with single TMD, and then increasing the numbers of TMDs one more at a time until the desired number is reached. Using the obtained design parameters, the effectiveness and robustness of the MTMDs are studied in comparison to MTMDs designed by previous works available in the literature. As a result, the proposed design procedure produces an effective multiple tuned mass damper to be utilized in a SDOF system under harmonic excitation. Additionally, the proposed approach provides a simple way to design the MTMD system than the traditional optimization methods, thus it significantly reduces the computation effort in the design process.
- MakaleYalnız künye2017Series tuned mass dampers in train-induced vibration control of railway bridges
Kahya, Volkan; Araz, Onur
This paper presents the series multiple tuned mass dampers (STMDs) to suppress the resonant vibrations of railway bridges under the passage of high-speed trains (HSTs). A STMD device consisting of two spring-mass-damper units connected each other in series is installed on the bridge. In solution, bridge is modeled as a simply-supported Euler-Bernoulli beam with constant cross-section, and vehicle is simulated as a series of moving forces with constant speed. By the assumed mode method, the governing equations of motion of the beam-TMD device coupled system traversed by a moving train are obtained. The optimum values for the parameters of the STMD device are obtained for the criterion based on the minimization of the maximum dynamic displacement of the beam at its midspan. Single TMD and multiple TMDs in parallel are also considered for demonstration of the STMD device's performance. The results show that STMDs are effective in bridge vibration suppression and robust to parameters' change in the main system and the absorber itself.