Banca de DEFESA: Leticia Nunes Lopes

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : Leticia Nunes Lopes
DATE: 04/08/2022
TIME: 14:30
LOCAL: TEAMS
TITLE:

FATIGUE AND RUTTING IN BINDER AND ASPHALT MIX WITH REACTED AND ACTIVATED RUBBER (RAR)

KEY WORDS:

1. Asphalt rubber                                                  

 2. Gap Graded

3. Uniaxial Cyclic Fatigue

4. Complex Moduli

5. S-VECD Model                                           

6. Permanent Deformation

PAGES: 214
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

The search for environmentally correct actions is directly related to the use of sustainable materials and needs technological advances so that they can add performance improvements without prejudice to the quality of the pavements. The pre-treated granulated rubber technologies are emerging as a new method to produce asphalt rubber mixtures. Among these technologies, the Reacted and Activated Rubber (RAR) was developed with the proposal of simplifying the production process (as carried out in the dry process) and obtaining superior asphalt mixture’s performance (produced by the wet process by field blend). This research aims to investigate the influence of the addition of RAR, in the proportion of 30%, on the mechanical performance of a conventional binder (CAP 50/70) and a gap graded hot asphalt mixture, produced in the laboratory. In the binders, the permanent deformation was evaluated according to the Multiple Stress Creep and Recovery test (MSCR) and the fatigue according to the Linear Amplitude Sweep test (LAS). In the mixtures, the permanent deformation was evaluated according to the uniaxial repeated load test (flow number-FN) and for fatigue the cyclic uniaxial tensio/compression test was implemented. The results of fatigue tests on the binder and mixture were applied to the Simplified Viscoelastic Continuum Damage (S-VECD) generating the so-called damage characteristic curves (CxS). In the mixtures, the calibration data of the S-VECD model and the viscoelastic properties allowed the simulation of a pavement structure in the FlexPAVE™ program. The modified binder showed an increase in resistance to the accumulation of permanent deformations and in traffic classification levels for all temperatures, in addition to greater fatigue tolerance, showing greater accumulation in the level of damage at failure. The modified mixture responded in accordance with the improvements observed in the binder, with higher FN and integrity values for the same level of accumulated damage. The analysis on FlexPAVE™ showed that the addition of RAR makes the performance of the mixture to fatigue less dependent on the applied thickness, presenting low values of average accumulated damage.

BANKING MEMBERS:
Presidente - 404227 - MARCIO MUNIZ DE FARIAS
Interna - 1519113 - MICHELE DAL TOE CASAGRANDE
Externo à Instituição - WASHINGTON PERES NUNEZ - UFRGS
Externo à Instituição - Luciano Pivoto Specht - UFSM