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The extraction and recovery of bitumens from bituminous mixtures is an important procedure in the paving industry. This work achieves to evaluate the rheological, permanent deformation and fatigue tests to calibration of the recovery procedure in the rotary evaporator. The protocol was divided in bitumens of known properties with laboratory aging and bitumens of unknown properties subjected to field aging. The materials were subjected to different distillation times and tested chemically, rheologically and for damage by fatigue and permanent deformation. The results indicated that the chemical FTIR test was not sensitive in capturing the presence of residual solvent in the bituminous materials due to low concentrations after recovery. The joint analysis of the |G*|, Jnr at 3.2 kPa of the MSCR and the Nf of the LAS test were consistent for determining the distillation times in the rotary evaporator to result in the absence of residual solvent and additional aging.

The guarantee of traffic conditions with safety and comfort is one of the primary aims during a road structure design. Thus,this study aims to contribute to the roughness prediction, represented by the International Roughness Index (IRI), bydeveloping models that describe the functional performance of Brazilian pavements. With monitoring actions carried out insites located in Santa Maria/RS and Rio de Janeiro/RJ, the paper sought to evaluate the IRI's evolution. The mechanisticmethodology was inserted to the study's scope by predicting the IRI evolution using the average fatigue damage, which wascalculated with FlexPAVETM software. The procedure enabled the development of a mechanistic-empirical model, basedon the initial IRI obtained after the end of the construction process and the computationally asphalt layers calculateddamage. The developed model was also validated with other sites within the Brazilian territory, which results in significantpractical applicability.

Fatigue cracking is one of the main failure modes in asphalt pavements, and is characterised by the accumulation of damage from traffic loading repetition. This research evaluated 24 asphalt mixtures effectively used in Brazilian highways. Hot and warm mixtures produced in plants were analysed, aiming to characterise and evaluate asphalt concretes with different aggregates, different types of binders and produced by different plants. Complex modulus and fatigue tests were performed. 2S2P1D rheological model (two springs, two parabolic elements and one dashpot) and the simplified viscoelastic continuum damage (S-VECD) model for fatigue were applied. The FlexPAVE™ software was used for analysis of pavement performance. The linear viscoleastic behaviour evaluation suggesting a higher stiffness of mixtures with conventional binder at low temperatures and high frequencies, and a greater stiffness of mixtures with polymer modified binder (PMB) for the domain of high temperatures and low frequencies. PMB and rubber asphalt mixtures generally have better fatigue performance than conventional binder mixtures. There are indications that more cubic and less lamellar aggregates provide better fatigue performance. As expected and reported in the literature, no correlations were found between viscoelastic linear behaviour and fatigue, except for a possible correlation with the phase angle master curve peak.

The objective of this research was to evaluate the rheological behaviour of twelve Brazilian bitumens and mixtures. Dense mixtures were produced with ten conventional and two modified bitumens. To measure the complex modulus, the frequency sweep tests in Dynamic Shear Rheometer (DSR) (G*) were carried out for bitumens and the compression complex modulus (E*) test were performed for mixtures. From the experimental results, the 2S2P1D modelling and Shift-Homothety-Shift and time-Shift (SHStS) were applied to verify the correspondence of LVE behaviours of related bitumens and mixtures. It was verified that the mixtures had similar values of the constants E0(glassy modulus) and E00(static modulus). In general, the mixtures presented different behaviours in terms of LVE. The parameters of the 2S2P1D model k, hand δ showed equal or similar values for the bitumen and mixture scales. The SHStS transformation presented successful predictions of mixtures LVE behaviour from bitumens LVE behaviour for nine of the twelve materials.

In order to minimise the impact on the environment of reclaimed asphalt paving (RAP) disposal, a policy was established in Brazil determining that such residue should be recycled and used in roadways whenever possible. Mixing RAP with powdered rock and Portland cement to be used as a base/sub-base of pavements has been experienced with interesting results. Though, there is a lack of studies on the mechanical properties (unconfined compressive – quand split tensile – qt) and the viscoelastic behaviour (dynamic modulus – E* and phase angle – δ) of RAP – powdered rock – Portland cement blends. The present research aims at quantifying the influence of amounts of Portland cement (C) and the effect of the porosity (η) of the compacted blend in improving qu, qtand E* of the mixtures. This paper advances in the understanding of the key parameters controlling strength and stiffness of compacted RAP – powdered rock – Portland cement mixtures by quantifying the influence of porosity/cement index (η/Civ) on quand qtstrengths and mainly on the viscoelastic behaviour (E* and δ), including the effect of frequency (F) and the testing temperatures (TT). A single qt/qurelationship equal to 0.17 was found, being independent of the η/Civ. On the other side, it is shown that η/Civis an appropriate parameter to assess both the E* and the quof the RAP – powdered rock – Portland cement mixtures studied. The phase angle (δ) of the compacted mix is not affected by η/Civ, being slightly influenced by Fand TT. It varies from a minimum of 3° at low testing temperatures and high frequency to a maximum of 14°.