Compósitos à base de rejeito do minério de ferro, resíduo de concreto, resíduos da produção de celulose e resíduo da produção da cal

Abstract

The present thesis refers to the development of new composites for civil construction, using as raw materials concrete waste (RC), waste from lime production (RPC), waste from cellulose production (RPCEL) and waste from ore iron (RMF), all of them with high alkalinity, above all RMF with pH 10.21 from the dam called “Fundão” in the municipality of Mariana MG. XRD, SEM and EDS tests were performed to explain the considerable resistance gain, following changes in mechanical properties, morphological structures and the physical-chemical processes of formation of new structures. During the period of 720 days, 1045 specimens were used, distributed in 19 compositions for the performance of the tests of: compressive strength, water resistance coefficient, water absorption by immersion and linear expansion coefficient, meeting the requirements Brazilian standards. The compositions number 16 and 17 stood out, since their properties are the most satisfactory among the others, obtaining their compressive strengths of 4.07MPa and 6.92MPa at 28 days of curing, proving the formation of the structures of the new materials. The increase in the values of the mechanical properties observed during the curing occurs due to the neutralization and dissolution of the surfaces now with low alkalinity with hydrogenic potential just above 7.50, causing the synthesis of the new amorphous and crystalline formations. Also to prove the efficiency of the composition 17, two realsize building materials were molded. The results of this thesis allow us to conclude that these associated industrial wastes, used in civil construction materials, contribute to reduce the extraction of natural resources, in addition to providing a correct destination for waste that is improperly deposited, offering constant danger to the environment and the society that lives around it. its surroundings.