Análise do desempenho à fadiga de ligantes e misturas asfálticas densas em função da origem e da modificação por polímero

• Ano de defesa: 2023
• Autor(a) principal: Raffler, Andréia
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Tecnológica Federal do Paraná; Curitiba; Brasil; Programa de Pós-Graduação em Engenharia Civil; UTFPR
• Palavras-chave em Português: Pavimentos de asfalto - Fadiga; Concreto asfáltico; Asfalto; Copolímeros; Misturas com emulsão asfáltica; Resistência de materiais - Testes; Deformações e tensões; Pavements, Asphalt - Fadigue; Asphalt concrete; Asphalt; Copolymers; Asphalt emulsion mixtures; Strength of materials - Testing; Strains and stresses; CNPQ::ENGENHARIAS::ENGENHARIA CIVIL; Engenharia Civil
• Link de acesso: http://repositorio.utfpr.edu.br/jspui/handle/1/33043

Brazilian asphalt pavements have been shown premature failure in the field, especially by fatigue cracking and rutting. This may be explained by factors such as superseded design methods. Despite the advances in Brazilian Highway Engineering with the advent of the new flexible pavement design method (MEDINA, in Portuguese), there are deficiencies in terms of publications that correlated the MEDINA fatigue mixture test protocol with the rheological tests for fatigue characterization of asphalt binders. In this manner, the general objective of the present study is to analyze the susceptibility of highly-modified asphalt binders and mixtures (HiMA) and the ones modified with the styrene-butadiene-styrene (SBS) to fatigue. In addition to Brazilian binders, materials from Russia and Colombia were also included in the investigation. The asphalt mixtures were fitted to a dense-graded curve labeled as “Band C” according to the National Department of Transport Infrastructure (DNIT, in Portuguese), and their design process followed the SUPERPAVE mixture design criterion. A fixed air voids content of 4% after 100 gyrations in the SUPERPAVE Gyratory Compactor was set to all formulations. The mechanical tests included splitting tensile strength, resilient modulus, IDEAL-CT and indirect tensile test for fatigue. The binder tests included the Linear Amplitude Sweep (LAS) test protocol and oscillatory shear test for the construction of master curves – both of them carried out in a Dynamic Shear Rheometer (DSR). The binders and mixtures were ranked according to their fatigue resistances, and linear correlations were constructed to analyze the feasibility of binder parameters in estimating the susceptibility of their corresponding mixtures to fatigue. The Colombian unmodified binder (AC 60-70 CO) showed a superior performance when compared with the Brazilian unmodified and SBS-modified binders, and this might be explained by the particular chemical composition of this material. The Russian SBS-modified binder (AMP 65/90 RU) provided a much better fatigue performance in comparison to the other studied binders, which suggests a good field performance of this material in the pavement. In addition to the Russian formulation, the Brazilian highly-modified binder (HiMA BR) also showed promising results in the fatigue tests and in both mixture and binder scales. In general, the Glower-Rowe (G-R) and Δtc parameters showed a limited applicability in this study because their correlations with the mixture fatigue parameters showed opposite trends, in comparison with previously published studies. Factors such as the aging level and the tests performed in the study may justify such conclusions.