Banca de DEFESA: Lucas Borchardt Ghedini

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Lucas Borchardt Ghedini
DATE: 30/01/2023
TIME: 14:00
LOCAL: UnB - FT/ENC - Defesa Remota via Teams
TITLE:

A STUDY OF VIBRATION ATTENUATION OF SHEAR BUILDINGS UNDER DYNAMIC LOADS USING TLCDS

KEY WORDS:

Structural Dynamics, Vibration Control, Tuned Liquid Column Damper, Parametric Analysis, DynaPy

PAGES: 84
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Estruturas
SPECIALTY: Mecânica das Estruturas
SUMMARY:

The problem of scarce construction area in the main and highly populated cities of the world has led to the use of tall buildings in the modern era. This serves as a way to allocate more space for homes, commerce, entrepreneurship and business. The use of lightweight and high strength materials along with advanced construction techniques have led to an incredible rise in the number of tall buildings, which tend to be slender, flexible and lightly damped structures. Because of that, they are very sensitive to environmental excitations such as winds and earthquakes. This also causes these types of structure to become more susceptible to the problems caused by unwanted vibrations, which could induce structural failure, occupant discomfort and malfunction of equipment. Even small vibrations, often times not offering risk to a building’s structural integrity, can cause extreme nuisance and discomfort to its inhabitants. Thus, it becomes important to search for practical and effective ways to reduce these vibration-related problems in the form of, for example, devices capable of controlling structure vibrations. The functioning of a passive device is focused on absorbing part of the energy of the structure to which it is coupled and dissipating this energy by its own mechanisms. One of these devices is the Tuned Liquid Column Damper (TLCD), which consists of a U-shaped tube partially filled with water. Part of the energy absorbed from the vibrating main system is dissipated by the movement of the liquid inside the tube. In this work, the efficiency of the TLCD in reducing structural vibration is analyzed. The analysis in the search for its ideal parameters is made by numerical and analytical methods, such as a parametric analysis. Software packages like DynaPy are used to perform simulations, generate data, model case studies and analyze situations that approximate practical examples and real-life scenarios, such as seismic excitations. Optimal TLCD parameters are presented via response map for reducing the structure's maximum permanent response to harmonic excitation and for reducing the structure's rms response to seismic excitation. The variation of the TLCD parameters presented by the response map is directly related to the force acting on the structure. However, it is verified that regardless of the acting force, there is an ideal frequency range to tune the TLCD where the greatest reductions in the primary system response are found. From the ideal liquid column parameters determined by the parametric analysis, structural response reductions of approximately 60% were achieved. This work also illustrates Dynapy’s multiple features as a tool for learning and teaching structural dynamics.

BANKING MEMBERS:
Interno - 707.843.298-34 - JOSE LUIS VITAL DE BRITO - UFRGS
Presidente - 404485 - LINEU JOSE PEDROSO
Externo à Instituição - PAULO MARCELO VIEIRA RIBEIRO - UFPE
Interno - 1550512 - RODRIGO DE MELO LAMEIRAS