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Authors
Advisor(s)
Abstract(s)
A reabilitação ou o reforço de estruturas são atividades que assumem um papel importante no controlo do
tempo de vida útil de uma estrutura. Neste contexto o pré-esforço, como tecnologia em crescimento e tendo em
conta que pode ser aplicado em diversas estruturas, estabelece uma das soluções alternativas para a
implementação em obras de engenharia.
Os silos e reservatórios são estruturas bastante comuns, estando os primeiros normalmente associados por
exemplo ao armazenamento de produtos agrícolas, cimento, biomassa e os segundos a funções de regularização
de caudais e de pressões, bem como a redes de abastecimento de água e rega.
Sabe-se que todas as estruturas envelhecem e sofrem alterações ao longo do tempo que podem torná-las
inadequadas ao seu uso. Dentro desta problemática, pretende-se com a presente dissertação, abordar a temática
da reabilitação e reforço de silos e reservatórios recorrendo à tecnologia do pré-esforço.
Deste modo, abordar-se-ão os principais campos de aplicação desta solução, identificando previamente os
principais problemas que ocorrem neste tipo de estruturas em betão armado, nomeadamente na corrosão das
armaduras, degradação do betão, deformações excessivas e eventual ocorrência de fissuras.
Pretende-se ainda falar das principais causas naturais, estruturais e acidentais que estas estruturas
habitualmente podem estar expostas.
Será apresentado um caso de estudo sobre um silo de armazenamento de farinha de cru, em que se
recorreu ao reforço estrutural por meio do pré-esforço exterior e a reparação com recurso de betão projetado por via
seca e com agregados grossos com máxima dimensão de 8 mm. Neste caso, justifica-se a escolha de pré-esforço
exterior como técnica de reforço do silo e realça-se a importância da necessidade de inspeções periódicas e da
compatibilidade entre o que se projeta e o que se constrói.
Rehabilitation or reinforcement of structures are activities that play an important role in controlling the useful life of a structure. In this context the pre-effort, as a growing technology and taking into account that it can be applied in several structures, establishes one of the alternative solutions for the implementation in engineering works. The silos and reservoirs are very common structures, the former usually being associated, for example, with the storage of agricultural products, cement, biomass, and the latter with flow and pressure regulation functions, as well as water supply and irrigation networks. It is known that all structures age and undergo changes over time that may make them unsuitable for their use. Within this problem, it is intended with the present dissertation, to approach the theme of the rehabilitation and reinforcement of silos and reservoirs using the technology of the pre-effort. In this way, the main fields of application of this solution will be addressed, identifying previously the main problems that occur in this type of structures in reinforced concrete, namely in the corrosion of the reinforcement, degradation of the concrete, excessive deformations and eventual cracks. It is also intended to talk about the main natural, structural and accidental causes that these structures can habitually be exposed. A case study will be presented on a storage silo of raw meal, in which the structural reinforcement was utilized by means of the external pre-stress and the repair with concrete resource projected by dry route and with aggregates thick with maximum dimension of 8 mm. In this case, the choice of external pre-stress as a silo strengthening technique is justified, and the importance of the need for periodic inspections and the compatibility between what is designed and what is built is emphasized.
Rehabilitation or reinforcement of structures are activities that play an important role in controlling the useful life of a structure. In this context the pre-effort, as a growing technology and taking into account that it can be applied in several structures, establishes one of the alternative solutions for the implementation in engineering works. The silos and reservoirs are very common structures, the former usually being associated, for example, with the storage of agricultural products, cement, biomass, and the latter with flow and pressure regulation functions, as well as water supply and irrigation networks. It is known that all structures age and undergo changes over time that may make them unsuitable for their use. Within this problem, it is intended with the present dissertation, to approach the theme of the rehabilitation and reinforcement of silos and reservoirs using the technology of the pre-effort. In this way, the main fields of application of this solution will be addressed, identifying previously the main problems that occur in this type of structures in reinforced concrete, namely in the corrosion of the reinforcement, degradation of the concrete, excessive deformations and eventual cracks. It is also intended to talk about the main natural, structural and accidental causes that these structures can habitually be exposed. A case study will be presented on a storage silo of raw meal, in which the structural reinforcement was utilized by means of the external pre-stress and the repair with concrete resource projected by dry route and with aggregates thick with maximum dimension of 8 mm. In this case, the choice of external pre-stress as a silo strengthening technique is justified, and the importance of the need for periodic inspections and the compatibility between what is designed and what is built is emphasized.
Description
Dissertação de natureza científica para a obtenção do grau de mestre em Engenharia Civil na Área de Especialização de Estruturas
Keywords
Reservatórios Tanks Pré-esforço por pós-tensão Pre-stress by post-tensioning Reabilitação Rehabilitation Reforço Reinforcement Silos
Citation
BAHU, Agnes Vissolela Alicerces - Reabilitação e reforço de silos e reservatórios, com recurso à tecnologia do pré-esforço. Lisboa: Instituto Superior de Engenharia de Lisboa, 2018. Dissertação de mestrado.
Publisher
Instituto Superior de Engenharia de Lisboa