Estudo dos mecanismos de transferência de tensões de cisalhamento em concreto reforçado com fibras de aço: análise do intertravamento de agregados

• Autor(a) principal: Lobo, Fausto Arantes
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000003x8g
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/12195
• topic: Concreto reforçado com fibras de aço; Cisalhamento; Intertravamento dos agregados; Steel fiber-reinforced concrete; Shear; Aggregate interlock; ENGENHARIAS::ENGENHARIA CIVIL::GEOTECNICA

It was performed an experimental analysis in order to evaluate the contribution of the steel fibers and the aggregate size in the shear strength of the concrete. This paper describes tests to evaluate the shear strength and a test method for evaluation of shear stress transfer by aggregates interlock. In the experimental development, it was used concrete with a mean strength of 60 MPa, with 9.50 mm and 12.50 mm coarse aggregate, varying the volume of steel fibers in 0%, 0.5% and 1.5%. The results showed that the methodology developed to evaluate the direct shear test with two planes worked well until the maximum force for all the models. The direct shear testing results for pre-cracked (push-off test) attested that the fibers contribute to the effect of the aggregates interlock by reducing the crack opening and the sliding of the interface for a given shear stress. Moreover, the aggregate size contributes to the increasing of the interface roughness and consequently in the increasing of shear stress transfer. In addition, it was proposed the modification in one of the empirical models used to evaluate the interlocking aggregate phenomenon in the concrete by considering the experimental value of shear strength concrete. This modified empirical model demonstrated good correlation with the shear stress versus dilatancy that was obtained experimentally.