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Materiais de engenharia, provindos de jazidas, vêm a cada dia perdendo espaço para materiais alternativos aplicados à indústria da construção. O impacto ambiental de desgaste do pavimento em condições normais é afetado pelo tipo e pelas porcentagens de materiais na mistura. Para mitigar os problemas de caráter ambiental causados pela extração de materiais de jazidas e pela destinação incorreta de descartes, empresas estão usando cada vez mais resíduo de pneu, conhecido como asfalto-borracha. O objetivo deste trabalho é ampliar o conhecimento quanto à aplicação de resíduos de construção em asfaltos assim como na produção de asfalto-borracha, diminuindo os problemas ambientais ocasionados pelo descarte de pneus em lugares inapropriados.

The use of wood residue in asphalt pavements is not common yet, but it is attributed to the gain of structural strength and the reuse of this material discarded in nature. The main objective of this work is the evaluation of asphalt coatings with hardwood residue and ground tire rubber. The methodology follows the steps of preparation and mechanical analysis of the asphalt compound, initially the shear of the mixture of ground rubber tire with sand and hardwood residue. Soon after, the mixture was made of composite with asphalt in the dry process, then the rheological characterization of these samples by means of the parallel plate rheometer, plate to plate of 35 mm in diameter. Then samples of hot mixed asphalt (HMA) made according to Marshall's dosage, modified and unmodified concretes with the compound under study. Micrograph tests were performed using optical microscopy and scanning electron microscopy (SEM). Finally, mechanical tests on Marshall specimens. The material under study was applied on the track, and this asphalt was monitored for 50 months. The results showed that hardwood residue was compatible with rubber residue and efficient in the rheological properties of petroleum asphalt cement. In mechanical tests, there was a gain of stability, a 15 % higher result for asphalt with wood and rubber residue and at 10 % higher values ​​of the empty asphalt bitumen-compost ratio compared to conventional asphalt concrete. Thus, the applicability of the studied composite is satisfactory and environmentally correct, when it comes to the reuse of materials that replace materials from natural deposits.

The objective of this research is to analyze the mechanical resistance to compression of conventional specimens and specimens with the addition of red ceramic and waste of ethylene poly terephthalate (PET). The methodology applied has been based on the experimental dosage method of the Sao Paulo State Technology Research Institute (IPT). Three traces have been made: rich trace (1:0.5:3.5:0.45), medium trace (1:0.8:4.2:0.54) and poor trace (1:1.1:4.9:0.65), with percentages 0%, 2%, 3% and 4% of recycled PET fiber mixed with the red ceramic waste. For concreting, the materials have been mixed in a concrete mixer with a capacity of 120 liters in 20 min for each trace. Like this, 36 specimens have been made in cylindrical form 10 cm in diameter and 20 cm in height, with ages of initially and 28 days, both before the breaking load test, spending the first 24 hours immersed in tanks with water, remaining until the day of its rupture, according to NBR 5738 (ABNT, 2008). Slump flow tests, T500 time tests, workability have been performed, as well as the mechanical tests of Compressive strength and Compressive strength/density. PET fiber/red ceramic has offered greater workability than conventional concrete aggregate, using the same w/c ratio. A 4–12% reduction in density has been achieved with the PET fiber/red ceramic compared to the conventional aggregate concrete. With the 4% PET fiber/red ceramic replacing conventional aggregates at a 0.45 a/c ratio, compressive strength of 37.56 MPa has been obtained, the highest among all traces.