Estudo das propriedades mecânicas de misturas asfálticas por microscopia de força atômica

• Ano de defesa: 2011
• Autor(a) principal: Costa, Erivelton Façanha da
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Microscópio de força atômica; Asfalto; Nanoindentação
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/11936

The rheological study of asphalt binders is of great importance for determining its performance in paving construction. Usually, rheological parameters are obtained by a Dynamic Shear Rheometer (DSR). The aim of this work is to study the rheological properties of bitumen using an Atomic Force Microscope (AFM). So, a computational tool caled FVLOAD was used for imaging processing. Five kinds of mathematical models were used in order to analise the force curves colected through AFM: the slope analysis, the Young´s model, the adesion model, the FIEL model (Force Integration to Equal Limits) and the work difference model. Three samples were studied: pure bitumen 50/70, bitumem 50/70 doped with 4% of EVA and bitumem 50/70 doped with 4,5% of SBS. Very thin lms of these materials were prepared on glass slides and lead to an AFM for imaging. The area studied on the sample surface was of 50 m x 50 m. There were colected 1024 force curves for each image. The indentations were carried out in four frequencies: 0,5 Hz, 5 Hz, 14 Hz e 28 Hz. The curves colected were analyzed with the FVLOAD program and once the elastic properties were calculated, they were compared to those obtained in the Dynamic Shear Rheometer.