Abstract:
In general, all materials used in the construction industry are subject to the influence of degradation mechanisms, which are characterized by a sequence of chemical, physical, and mechanical changes. In the case of reinforced concrete elements strengthened with composite materials, it is generally observed that degradation affects the most sensitive part of the strengthening system, the epoxy adhesives. This study is based on the use of the Accelerated Conditioning Protocol (ACP) presented by ACI 440.9R (AMERICAN…, 2015) for the evaluation of the durability of reinforced concrete beams flexurally strengthened with CFRP sheets applied according to the EBR technique. The results of the ACP were compared with those obtained through natural weathering tests. The results showed that epoxy adhesives had their mechanical properties significantly reduced, while the CFRP composites remained unchanged after exposure to weathering or to accelerated degradation. The strengthening system greatly increased the load carrying capacity and stiffness of the beams. However, the tests carried out after an accelerated degradation cycle lasting 1,000 h (42 days) and those carried out after 6 months’ exposure to weathering showed a reduction of approximately 10% in the load carrying capacity of the strengthened elements, indicating a possible degradation of the strengthening system.
Reference:
DALFRÉ, Glaucia Maria; SARTI JUNIOR, Luiz Antônio; ARAÚJO, Ciro José Ribeiro Villela. Protocolo acelerado de degradação do sistema de reforço EBR-CFRP aplicado em vigas de concreto armado. Ambiente Construído, v.21, v.3, p.47-63, jul./set., 2021.
Access to the article on the Journal website:
https://www.scielo.br/j/ac/a/g9mJ4DGPSMSwqRMzK537RjM/
In general, all materials used in the construction industry are subject to the influence of degradation mechanisms, which are characterized by a sequence of chemical, physical, and mechanical changes. In the case of reinforced concrete elements strengthened with composite materials, it is generally observed that degradation affects the most sensitive part of the strengthening system, the epoxy adhesives. This study is based on the use of the Accelerated Conditioning Protocol (ACP) presented by ACI 440.9R (AMERICAN…, 2015) for the evaluation of the durability of reinforced concrete beams flexurally strengthened with CFRP sheets applied according to the EBR technique. The results of the ACP were compared with those obtained through natural weathering tests. The results showed that epoxy adhesives had their mechanical properties significantly reduced, while the CFRP composites remained unchanged after exposure to weathering or to accelerated degradation. The strengthening system greatly increased the load carrying capacity and stiffness of the beams. However, the tests carried out after an accelerated degradation cycle lasting 1,000 h (42 days) and those carried out after 6 months’ exposure to weathering showed a reduction of approximately 10% in the load carrying capacity of the strengthened elements, indicating a possible degradation of the strengthening system.
Reference:
DALFRÉ, Glaucia Maria; SARTI JUNIOR, Luiz Antônio; ARAÚJO, Ciro José Ribeiro Villela. Protocolo acelerado de degradação do sistema de reforço EBR-CFRP aplicado em vigas de concreto armado. Ambiente Construído, v.21, v.3, p.47-63, jul./set., 2021.
Access to the article on the Journal website:
https://www.scielo.br/j/ac/a/g9mJ4DGPSMSwqRMzK537RjM/
