Análise do envelhecimento, rigidez e suscetibilidade á presença de água em misturas recicladas com adição de agentes de reciclagem.

Abstract

Usually, the restoration of a pavement involves the steps of milling the worn coating and applying a new layer. Milling is a mechanical process of cutting the floor covering that generates a residue called milled. The main alternatives for the reuse of this material in the paving area are the use as a stabilizer of bases and sub-bases or as an integral part of the asphalt mixture. The preparation of recycled mixtures must consider the presence of the aged binder, otherwise the recycled mixture will present low resistance to cracking. The recycled mix design guidelines recommend rejuvenating the oxidized binder through the addition of recycling agents (RA), which are viscosity and therefore temperature reducing additives. Because it is a component of recent use in paving and its variety, there is no consensus on the determination of the AR content or the ideal moment of its addition in the mixing process of recycled asphalts. The lack of agreement is due to the difficulty in analyzing the interaction between the various ARs and the aging binder present in the milled material. This study aimed to analyze asphalt mixtures with the addition of high levels of RAP (25%, 50%, 75% and 100%), of different types of recycling agents (ADCAP WM and residual engine oil) and in different stages of the production of recycled asphalt mix (next to milled, next to aggregate and in addition to binder). The results indicated that it is possible to use up to 75% of milled material in recycled asphalt mixtures, however, a detailed monitoring of its execution and performance throughout its useful life is necessary. By adding residual engine oil it is possible to make recycled mixtures with additions of 50 and 75% milled, provided that the addition of residual oil is made directly to the new binder. In the case of ADCAP WM additions, the same additions can be performed and the addition configurations can be added by adding the recycling agent to the aggregate. Through the analyzes carried out in this thesis, it is possible to state that the maximum RAP content to be applied should be 75%, the best additive, between the two used, is ADCAP WM, and the addition directly to the binder showed slightly better results.