Termografia infravermelha para avaliação de danos em obras de arte especiais de concreto armado

• Ano de defesa: 2020
• Autor(a) principal: Pozzer, Sandra
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade de Passo Fundo; Brasil; UPF; Programa de Pós-Graduação em Engenharia Civil e Ambiental; Instituto de Tecnologia
• Palavras-chave em Português: Engenharia civil; Concreto armado - Estrutura; Concreto armado - Inspeção; Testes não-destrutivos; Engenharias::Engenharia Civil
• Link de acesso: https://repositorio.upf.br/handle/123456789/9636

Structural management is one of the continuous engineering challenges, where in addition to the project and construction there is a constant concern to ensure reliability in the performance of the structures. The inspections have been an important activity in the structure management, which allows diagnoses and prognoses based on the structural, functional and durability conservation state of the elements. In this context, is increasing the use of non-destructive testing to minimize the inspection damages and to optimize the inspection procedure. This study approached a qualitative and quantitative performance analysis of passive infrared thermography as a non-destructive test for inspections of concrete structures. Three samples of bridge slabs and one sample of bridge column were fabricated, which included the simulation of different subsurface damage configurations, and tested using passive infrared thermography at different times of day and year. A statistical approach was developed, where a multivariate regression analysis was used to explain and predict the thermal behavior of the inspected areas. Within the study horizon, periods between 12:00 noon and 4:00 in the afternoon, with temperatures between 27.5°C and 37.9°C, a large amount of direct solar radiation and low atmospheric pressure set the ideal scenario for thermographic inspections in reinforced concrete bridge under passive heating. In addition, months with hotter weather (November and February) allowed detecting a greater amount of robust thermal contrasts than months of colder weather (March, April, June, and July). A numerical simulation using finite element model was performed to test the use of the computational tool in the field of passive infrared thermography and has successfully replicated the thermographic inspections using solar radiation, with convergent observed and simulated results of both thermograms and contrast values, and an average difference of just 0.2°C. In general, the passive infrared thermography technique was capable of detect delaminations in inspection of reinforced concrete bridge slabs and columns samples, being especially sensitive to the environmental conditions.