Estudo numérico da absorção vibracional considerando o efeito periódico de fundação em uma estrutura de pequeno porte

Abstract

The growth of urban areas has led to buildings getting closer and closer to road traffic routes. This scenario exposes structures to vibrations generated by the flow of loads, causing discomfort to occupants and even structural damage, such as cracks and the risk of collapse. Although there are numerical studies on traffic vibrations, vibration isolation techniques are little explored in these studies. A promissory approach is the use of periodic structures, which act as filters absorbing unwanted frequencies and preventing their interference in the structure. Although used in several areas of engineering, periodic structures still have limited application in civil engineering, especially for isolating vibrations caused by vehicles rolling on the pavement in small-door buildings. In this context, this research developed three numerical finite element models for a small structure, which represent residential and/or commercial buildings with a number of floors equal to or less than three, in reinforced concrete. The first model included a block-type periodic structure foundation, while the two comparative models included radial-type periodic foundations and block-type concrete foundations. The objective was to analyze the vibrational absorption of different foundations. In order to compare and observe the beneficial benefits of using a periodic foundation, in the context of the study. The methodology employed consists of creating structural models using finite elements, establishing boundary conditions to couple the foundation layers and the structure, and guaranteeing guarantee. The study sought modal and frequency-domain responses resulting from foundation motivation, using the Ansys® (2023) software for all simulations. The results revealed that periodic foundations are able to reduce amplitude peaks at frequencies above 30 Hz, which is beneficial to attenuate vibrations in this range. With an adequate project, adjusting the geometric and physical parameters of the materials, it is possible to obtain an effective vibrational isolation for the structures, minimizing the vibrations from the ground waves in buildings. This indicates that the use of periodic structures shows great potential regarding the isolation of vibrations caused by traffic in small structures.