Caracterização de misturas de rejeitos de minério de ferro melhoradas com adição de cimento com vistas à aplicação em estradas e aterros

• Autor(a) principal: Oliveira, Tales Moreira de
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3807
• topic: Rejeitos de minério de ferro; Pavimentação; Melhoramento de solos; Iron ore tailings; Paving; Improvement of soil; CNPQ::ENGENHARIAS::ENGENHARIA CIVIL

This study conducted an array of tests to characterize the physic-mechanical and hydraulic properties of mixtures of iron ore tailings from the processing of iron ore, with and without addition of CP II-E-32 Portland cement with slag, aiming the application in layers of road pavements and construction of embankments. Tailing samples were obtained from specific points of iron ore processing by flotation and magnetic concentration. Tailings were termed flotation and concentration and collected from the processing plant Alegria, owned by Companhia Vale S.A. To meet the proposed goals were evaluated geotechnical parameters used in the characterization of pavement layers by means of an experimental program that included the following laboratory tests: (i) particle size tests, (ii) Atterberg limits (LL and LP), (iii) solid unit weight (iv) compaction, (v) CBR, (vi) compressive strength, (vii) analysis of immersion of specimens, (viii) durability by wetting and drying, (ix) permeability (x) application of the MCT methodology (Mini-MCV compaction and weight loss by immersion). The mixture with highest CBR value, with 60% flotation + 40% concentration, was identified by the TRB classification system and classified as A-4(1) and exhibited particle size composition compatible for use as a sub-base material according to DNIT specifications (2006). Nevertheless, it has a coefficient of uniformity between 5 and 6, which indicates a uniform grain size, reflecting negatively on the hydromechanical behavior. For application as a pavement base, the mixture should be studied with an increase of 8.5% cement, percentage determined by this work, to meet the average strength of 2.1 MPa, required for soil-cement mixtures according to ABCP (1980).