In the last few years, there has been a great focus on human health and improving working conditions. Within this context, it is necessary to study the impact of the highway construction on the quality of life of workers and the environment. This paper aims to study polycyclic aromatic hydrocarbons (PAHs) emission from different bitumens commercialised in Brazil (conventional, modified by polymer or rubber and natural asphalt). The bitumens were submitted to conventional (Brazilian specifications) and rheological (SUPERPAVE classification) tests. The most usual application method is as a hot mixture. When heated, the bitumen releases volatile species and solid particles carried by gases, and this mixture is called bitumen emissions. In this fume, there are organic substances (PAHs), some of which may be carcinogenic. Therefore, the fume emitted during bitumen heating is harmful to health and should be considered both from the environmental sustainability and the worker health points of view. PAH studies were done alongside with other studies where the bitumen and the emission of some PAHs were correlated, which were measured through an experimental apparatus that generates and collects the bitumen fume. The equipment used was a nominated extraction and collection device (ECD) and the tests were conducted on laboratory benches. The fumes were collected in ECD and analysed by liquid chromatography–mass spectrometry to quantify the amount of emitted PAHs. From the research, it was possible to verify if bitumens with different behaviours at paving, from the perspective of sustainability and different impacts to the environment and human health. These emissions have an impact on health and the environment, which require further understanding.

O presente artigo apresenta o estudo do comportamento de quatro solos com origens geológicas diferentes, quanto à sua resistência e deformação resiliente, comumente empregados em subleitos rodoviários no estado do Rio Grande do Sul. A metodologia aplicada consistiu em ensaios de caracterização física e mecânica, obtenção da curva característica dos solos, além de simulações numéricas assistidas por dois programas computacionais: AEMC e AASHTOWare Pavement ME Design. Os resultados indicaram que os limites descritos em norma para utilização dos solos como material de subleito foram satisfeitos. Verificou-se que uma variação de ± 2% no teor de umidade provocou considerável alteração na resistência desses materiais, evidenciando a influência da sucção na resistência ao cisalhamento dos solos. As análises mecanicistas permitiram constatar a limitação do método de dimensionamento do DNIT, principalmente no que tange à ruptura por fadiga, além de destacar a importância do módulo de resiliência no comportamento da estrutura como um todo.

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, h and 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.

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), by developing models that describe the functional performance of Brazilian pavements. With monitoring actions carried out in sites located in Santa Maria/RS and Rio de Janeiro/RJ, the paper sought to evaluate the IRI's evolution. The mechanistic methodology was inserted to the study's scope by predicting the IRI evolution using the average fatigue damage, which was calculated with FlexPAVETM software. The procedure enabled the development of a mechanistic-empirical model, based on the initial IRI obtained after the end of the construction process and the computationally asphalt layers calculated damage. The developed model was also validated with other sites within the Brazilian territory, which results in significant practical applicability.