In this research work, our goal is to test vibration mitigation and seismic devices for slender parametric structures subject to winds, seismic induced vibrations, and vehicular traffic. The obtained results will allow us to extend this experimental approach to other and more complex structures, such as long-span bridges. Our test-rig consists of a shaking table (designed in our labs) capable of supporting different types of structures. We designed a tuned liquid damper (TLD) with the purpose of mitigating vibrations in a vertical irregular three-story structure. We used aluminum bars for the modeling the stories and harmonic steel bars for the beams. For the shaking table, we used a solid block of aluminum weighing around 130 kg. On both sides of the frame, there are Hiwin guides, with two carriages each, on which we mounted a sled made of bosh profiles. We actuate the vibrating table with an electrody-namic shaker of Brüel & Kjær. The wave generator Textronix Arbitrary Function Generator AFG320 generates the signal and the power amplifier Brüel & Kjær-Type 2732 amplifies the signal. On each floor of the structure, we installed Brüel & Kjær Type 4371 accelerometers for acquiring the acceleration time history of the structure. We created a 3 degrees of freedom (DoF) lumped-mass model for evaluating the natural frequencies of the system and validated these data by a hammer impact test. We were able to set the sloshing frequency of the TLD by using the equation proposed by Housner. We studied the structure by positioning the TLD on each floor, at the same input frequency. Our results demonstrate the excellent capability of an appropriately sized TLD to mitigate vibrations under resonance conditions.
|Titolo:||Experimental investigation on structural vibrations by a new shaking table|
DE SIMONE, MARCO CLAUDIO [Investigation] (Corresponding)
GUIDA, Domenico [Supervision]
|Data di pubblicazione:||2020|
|Appare nelle tipologie:||4.1.1 Proceedings con DOI|