Utiliza??o de esc?ria de ferron?quel na composi??o de concreto betuminoso usinado ? quente.

Programa de P?s-Gradua??o em Geotecnia. N?cleo de Geotecnia, Escola de Minas, Universidade Federal de Ouro Preto.A crescente preocupa??o em minimizar a disposi??o de res?duos na natureza de forma desordenada, vem influenciando medidas que busquem dar novos fins ambientalmente sustent?veis e economicamente vi?veis a esses materiais. A utiliza??o de agregado sider?rgico na pavimenta??o rodovi?ria surge como alternativa ? redu??o da estocagem desse material nos p?tios sider?rgicos e ainda contribui com a diminui??o sinos custos da constru??o do pavimento rodovi?rio flex?vel em regi?es onde h? a disponibilidade desse material. O presente trabalho teve como objetivo verificar a viabilidade t?cnica do emprego da esc?ria de ferron?quel proveniente da mina de On?a Puma no estado do Par?, como agregado na composi??o de concreto betuminoso usinado ? quente (CBUQ). Para tanto, foram executados ensaios de caracteriza??o f?sica, qu?mica, mineral?gica e ambiental da esc?ria de ferron?quel e tamb?m a completa caracteriza??o do CAP 50/70. As misturas asf?lticas foram dosadas em concord?ncia com a metodologia Marshall, empregando-se a Faixa C do DNIT 031/2006 com a utiliza??o da esc?ria de ferron?quel nas por??es granulom?tricas correspondentes ? agregado gra?do, mi?do e f?ler, al?m do CAP 50/70. Ap?s a dosagem, a mistura correspondente ao teor de projeto de 6,0%, foi caracterizada mecanicamente por meio dos ensaios de m?dulo de resili?ncia, resist?ncia ? tra??o est?tica por compress?o diametral, fadiga por compress?o diametral ? tens?o controlada e deforma??o permanente por compress?o axial (creep est?tico). Com base nos resultados, afirma-se que a esc?ria de ferron?quel demonstra viabilidade t?cnica para ser utilizada como agregado na composi??o de concreto betuminoso usinado ? quente, cumprindo os requisitos estabelecidos pela normatiza??o brasileira.The growing concern in minimizing the disposal of waste in nature in a disorderly manner has been influencing measures that seek to give new environmentally sustainable and economically viable purposes to these materials. The use of steel aggregate in road paving emerges as an alternative to reducing the storage of this material in steel yards and also contributes to a significant reduction in the cost of building a flexible road pavement. This study aimed to verify the technical feasibility of using ferronickel slag from the On?a Puma mine as an aggregate in the composition of hot mix asphalt. To this end, physical, chemical, mineralogical and environmental characterization tests of ferronickel slag were performed, as well as the complete characterization of CAP 50/70. The asphalt mixtures were dosed in accordance with the Marshall methodology, using the DNIT Range C with the use of ferronickel slag in the granulometric portions corresponding to the coarse aggregate, fine aggregate and filler, besides the PAC 50/70. After the dosage, the mixture corresponding to the the optimum asphalt binder content of 6,0% was mechanically characterized by means of the tests of resilience modulus, static tensile strength by diametrical compression, fatigue by diametrical compression at controlled stress and permanent deformation by axial compression (static creep). Based on the results, it is stated that ferronickel slag demonstrates technical feasibility to be used as an aggregate in the composition of hot machined bituminous concrete, meeting the requirements established by Brazilian standardization. In addition, it is an excellent environmental alternative because it uses a material previously treated as an environmental liability, avoiding the exploration of new natural deposits of stone aggregates