Banca de QUALIFICAÇÃO: TATHIANA RODRIGUES CAETANO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : TATHIANA RODRIGUES CAETANO
DATE: 26/10/2021
TIME: 08:30
LOCAL: Sala do RNP
TITLE:

Tracking water losses in water pipelines by electroresistivity

KEY WORDS:

Water leaks. Detection of leaks. Applied geophysics. ERT.

PAGES: 70
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Engenharia Hidráulica
SPECIALTY: Hidráulica
SUMMARY:

Brazil has been suffering from water scarcity despite holding a considerable percentage of the world's available fresh water. To solve this problem, several measures are being studied, including ways to improve water supply systems. These systems are susceptible to leakage losses, and these exist in every country in the world. In Denmark the water loss is about 7%, in the UK 20%, in South Africa 35%, in Italy and Portugal 36%, and in Brazil the water loss is about 39% of the total treated water in the country. The focus of this study is to analyze how geophysical methods, especially electrical resistivity (ERT), can assist in identifying leaks, helping to mitigate problems related to water loss in water mains. The study will provide subsidies for a proposal of environmentally sustainable solutions for the maintenance of structures used to transport drinking water, as well as the stability of the subsurface, in which the hydraulic structure is inserted. ERT is a geophysical method that measures the electrical resistivity of the medium passed through by an electric current. For this, the equipment has electrodes that emit the electric current and allow the measurement of the electric potential (DV). The present proposal foresees the application of the ERT technique in two formats: (1) the first in conditions traditionally used to identify problems in the subsurface, i.e., with electrodes on the ground near the leaking pipe and (2) the second, in conditions not normally applied for this type of problem, with one of the electrodes placed inside the pipe. This work supports the hypothesis that the conduction of the electric current in the water, inside the pipe, will provide an electric field more directed to the location of the leak, which will make the second method more accurate than the first. This is intended to answer the following questions: (1) Are the problems related to leaks in treated water pipes the same that occur in Brazil? (2) What are the leak tracing techniques applied internationally and in Brazil? (3) Is there any relationship between leakage problems in treated water pipelines and their hydraulic functioning as well as their construction materials? (4) How accurate is ERT in identifying water pipeline leaks? (5) Is the accuracy achieved comparable with other geophysical techniques that can be applied to pipeline leakage? (6) Does the application of ERT in the new format provide better accuracy than usual format for different soil conditions, leak location and pipe shape, in laboratory situations on pipes filled with static water load? (7) Does the application of ERT in the new format provide better accuracy than usual format for different soil conditions, leak location and pipe shape, in numerical situations considering internal water flow within the pipe? To this end, field applications of ERT and other geophysical techniques, simulations with multiphysics finite element software, and application of statistical and metrological techniques to evaluate the accuracy of the methods will be performed.

BANKING MEMBERS:
Presidente - HERSILIA DE ANDRADE E SANTOS
Interno - REMKE LEANDER VAN DAM - CEFET-MG
Interno - ROGERIO CABRAL DE AZEVEDO
Externo ao Programa - FREDERICO ROMAGNOLI SILVEIRA LIMA
Externo à Instituição - VAGNER ROBERTO ELIS - USP