Previsão de vida útil de estruturas de concreto armado submetidas à ação de ions cloretos: modelagem numérica e aplicações

• Autor(a) principal: Moreira, Adrianne Lúcia Ribeiro
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/10893
• topic: Engenharia Civil; Concreto - Deterioração; Concreto armado; Método dos elementos finitos; Pontes de concreto; Íons - Cloretos; 624

Corrosion of concrete reinforcement due to penetration of chloride ions is one of the major causes of premature deterioration of structures. The durability and useful life of concrete structures are directly affected by the corrosion of the reinforcement. In addition to the importance of structural safety, the useful life of reinforced concrete structures plays an important role in sustainable development. From the point of view of durable projects, knowledge of deterioration mechanisms and the development of a tool based on the performance of the structure are essential to ensure safety, the execution of durable structures and the identification of appropriate measures to maintain the life of structures, as well as a rational approach to the repair of damaged structures. More sophisticated durability models should be considered for design and to estimate the life of the structure, especially in aggressive environments, considering the type of cement and reducing material consumption through the optimum concrete cover and proper choice of materials. Therefore, a numerical tool is desirable for predicting the useful life of concrete structures, which can more realistically demonstrate corrosion processes and their consequences on concrete performance. Thus, this work describes a numerical model to predict the useful life of concrete structures. The main objective of this study is to develop a numerical model and demonstrate its use in some applications. The diffusion of chlorides is implemented with the finite element method in the twodimensional domain and its formulation is presented. Temperature and moisture flux at the location of the structure is considered in the model coupled with the diffusion of chloride ions. The numerical model is compared to other numerical models and Fick's 2nd Law analytical solutions to verify their reliability. In addition, the use of the model is demonstrated for the provision of useful life for different concrete, demonstrating the importance of choosing the concrete for the useful life of the structure. Finally, this dissertation clarifies the use of predictive numerical models for the corrosion of concrete reinforcement, offering a tool to assist in decision making for the design of new structures or the planning of an existing structure.