Banca de QUALIFICAÇÃO: LINCOLN ALEXANDRE PAZ SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : LINCOLN ALEXANDRE PAZ SILVA
DATE: 05/12/2023
TIME: 14:00
LOCAL: https://meet.google.com/okv-mtxe-gqf
TITLE:

Autonomous Relative Humidity Monitoring System for Hollow Concrete Blocks

KEY WORDS:

Structural health monitoring; Radiofrequency sensors; Structural damage prevention

PAGES: 109
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUBÁREA: Telecomunicações
SPECIALTY: Teoria Eletromagnetica, Microondas, Propagação de Ondas, Antenas
SUMMARY:

The concept of structural health monitoring refers to a set of techniques capable of diagnosing and preventing damage in various engineering structures through continuous monitoring. Typically, the occurrence of damage is associated with the application of mechanical or environmental forces beyond the limits supported by the structure. Regardless of the type of force involved, the continuous and uncontrolled occurrence of damage is harmful to any structure and can even lead to its collapse. In buildings made of masonry and concrete, for example, excess moisture can lead to material deterioration through a process called carbonation, resulting in structural, economic, and health-related damage. An example of a monitoring technique described in the literature that can assist in identifying humid areas in buildings is based on the use of frequency or radiofrequency scanning sensors. These sensors provide a measurement of relative humidity in a non-destructive and indirect manner by correlating changes in the properties of an electromagnetic signal
transmitted through the analyzed structure with the monitored parameter. Although other techniques can be used for this purpose, radiofrequency sensing stands out for allowing the detection of parameters both on the surface and within the structure. In this context, the aim of this project is to develop an autonomous structural health monitoring system capable of measuring relative humidity in hollow concrete blocks, which are common
construction elements in buildings. The proposed system is based on the radiofrequency sensing technique and consists of two electronic circuits coupled to microstrip antennas for signal transmission and reception, along with a frequency-selective surface (FSS) for electromagnetic signal filtering. This frequency-selective surface is placed in direct contact with the concrete blocks, allowing it to be influenced by variations in relative humidity. Thus, sensing is established through the correlation between the block’s relative humidity and the power of the signal transmitted through the FSS-block assembly. The designs of the electronic circuits, antennas, and frequency-selective surface are presented. Preliminary results indicate that the selected frequency-selective surface is suitable for the application, and the receiving circuit was able to provide accurate voltage measurements in relation to the received signal power. Both results suggest that the proposed system is
feasible.

COMMITTEE MEMBERS:
Presidente - 2524053 - ANTONIO LUIZ PEREIRA DE SIQUEIRA CAMPOS
Interno - 1422265 - JOSE PATROCINIO DA SILVA
Externo ao Programa - 1840342 - MARCIO EDUARDO DA COSTA RODRIGUES - UFRNExterno à Instituição - HUMBERTO DIONISIO DE ANDRADE - UFERSA