Banca de DEFESA: Lara Cordeiro Pitangui

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Lara Cordeiro Pitangui
DATE: 10/10/2022
TIME: 15:30
LOCAL: Universidade de Brasília (SG12) e Teams.
TITLE:

Sustainable pavement performance with use of milled material and asphalt foam

KEY WORDS:

Asphalt foam; Test sections; Stabilized mixtures; Sustainable Pavements.

PAGES: 117
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

The use of milled material by reusing the asphalt coating of old pavement layers has been presented as a sustainable solution, capable of generating economic benefits and improvements related to environmental aspects. Looking for to encourage the use of milled material in its different possibilities, an Experimental Test Section was implemented with three experimental subsections on the SP-270 highway, under the administration of the Auto Raposo Tavares Concessionaire (CART), using a stabilized mixture with foamed asphalt in the base layer of the road SP-270, aiming to monitoring its performance in the face of traffic and weather. The three subsections had the base layer with the stabilized mixture, and the thickness of the base layer was reduced for test sections 2 and 3, when compared to test section 1, which had the original solution of the highway's project. The test sections were monitored through quality functional and structural assurance, with emphasis on permanent deformation on wheel track, cracking evaluation and deflectometric control with the Benkelman Beam and the Falling Weight Deflectometer (FWD). The materials of all pavement layers were evaluated through laboratory tests requested in the current design methods, with emphasis on the National Dimensioning Method – MeDiNa. The material of the subgrade and the base was evaluated by means of repeated load triaxial testing, in order to obtain permanent deformation and resilience’s modulus, and the base's material was still evaluated by different curing periods. In the asphalt coating layer, the resilience modulus test was also carried out. Through the evaluations in the field, the material has a good behavior, not showing cracking in any of the section in the period which it was evaluated, with the permanent deformation of the wheel track being the most observed defect. Also, about the mixture stabilized with foamed asphalt, it was seen that there is an increase in the stiffness of the layer over time, observed through the reduction of the deflections of section 1 and, also, through retroanalyses carried out at the beginning and after an evaluation period, which showed an increase in the layers in situ resilience modulus. For sections 2 and 3, no reductions in deflection were observed, but, even so, there was an increase in base layer stiffness, adding to the absence of cracking in both sections, even undersized. Through laboratory tests, it was found, by the resilience modulus, that the stabilized mixture with foamed asphalt has a very similar behavior of a granular material, dependent on the confining stress, being able to return satisfactory performance models when evaluated by means of these mechanical tests. Regarding the curing method studied, it was also dependent on the temperature and the number of days used for curing, being still essential to define which curing method best represents the behavior of the material in the field. Finally, through an evaluation with MeDiNa, it was seen that for the program use, it is necessary to include this type of solution in the database, aiming at a more specific calibration, since the transfer function current is not able to return an assertive damage evolution for this pavement.

BANKING MEMBERS:
Interno - 2517970 - GREGORIO LUIS SILVA ARAUJO
Externa à Instituição - LAURA MARIA GORETTI DA MOTTA - UFRJ
Interno - 404227 - MARCIO MUNIZ DE FARIAS
Presidente - 3132829 - RAFAEL CERQUEIRA SILVA