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The surface effect that hinders the dispersion of nanomaterials in the asphalt binder due to the large surface area and small particle size should be investigated. Thus, this study evaluates the effect of the incorporation of superficially modified zinc oxide nanoparticles (ZnO M) by 3-(2.3-epoxypropoxy)propyl trimethoxysilane (GPTMS) in the asphalt binder with 50/70 penetration index. The additive was incorporated in contents of 3%, 5%, and 7% in weight of the bind through physical and rheological tests. Penetration tests, softening point, rotational viscosity, performance grade (PG) – before and after rolling thin film oven (RTFO), multiple stress creep and recovery (MSCR), linear amplitude sweep (LAS), and master curve were performed. The addition of ZnO M nanoparticles provided the asphalt binder with more resistance to aging and oxidation in almost all properties analysed. In addition, the ZnO M increased resistance to permanent deformation, temperature field, and the integrity of the asphalt binder, thus increasing its fatigue life.

Reactive and nonreactive polymers and polyphosphoric acid are options used as modifiers of asphalt binders whose objective is to improve the mechanical properties of the asphalt mixture. This research evaluated the mechanical behavior of asphalt mixtures modified by reactive/nonreactive polymer associated with polyphosphoric acid as a catalyst with different contents. The asphalt binder modifier polymers used were Ethylene Methyl Acrylate and Glycidyl Methacrylate (EMA-GMA), High-Density Terpolymer (HDPE), and Polyphosphoric Acid (PPA116%). Asphalt binder modified by styrene–butadiene–styrene (SBS) (AB 55/75) and penetration 50/70 asphalt binder (AB 50/70), the latter being the binder modified by polymers for analysis, were submitted to empirical and rheological physical tests before and after short-term aging (RTFO). The mixtures were dosed with the asphalt binders AB 55/75 and AB 50/70 without modification and modified by 1.8%EMA-GMA and 0.3%HDPE mixed with varying 0.3 and 0.5% of PPA116%. In addition, the mechanical tests of tensile strength, induced moisture damage, Cantabro wear, resilient modulus, dynamic modulus, and flow number were performed to evaluate the mechanical behavior of asphalt mixtures. Thet-Student statistical test verified the significance of the mechanical data of the mixtures. The results showed that the mixture modified with 1.8%EMA-GMA and 0.3%HDPE associated with 0.3% of PPA116% showed more excellent resistance to breaking strength, traction, susceptibility to moisture, more excellent resistance to wear, and resilient modulus, presenting values close to the sample with 0.5% of PPA116% in the dynamic modulus and flow number tests. These mixtures can be used as an alternative in regions with high temperatures.

This research's objective is to investigate the feasibility of incorporating polyethylene terephthalate (PET) into structural concrete blocks for use in civil construction. Initially, the materials were subjected to physical, chemical, and mineralogical characterization. Molded concrete blocks with dimensions of 14 cm × 19 cm × 29 cm, containing 2.5%, 5.0%, 7.5%, and 10.0% PET as a substitute for fine aggregate were used for the determination of physical and mechanical properties. It was observed that PET caused an increase in absorption and a reduction in the specific weight of structural concrete blocks. Furthermore, for compressive strength has been observed that PET reduced the strength of structural concrete blocks. PET caused mass variation, both for resistance to attack by sulfates, and to the action of rain. It did not change the acoustic behavior of the concrete when compared to the reference structural concrete block. The addition of PET resulted in more pores and hindered cement hydration. However, for PET contents of 2.5% and 5.0%, the values obtained for the characteristic resistance allowed us to classify them as class B structural blocks, with structural function for use in masonry elements above the ground level. Therefore, in the percentages and conditions established in this research, it is feasible from a technical point of view to use micronized PET to produce structural masonry blocks.

In Brazil, the traditional pavement design method by the National Department of Infrastructure and Transportation (DNIT) overlooks the mechanical performance of asphalt mixtures. As technological advancements in asphalt materials continue, understanding how variations in asphalt mixture compositions affect pavement durability and thickness using the new National Pavement Dimensioning Method (MeDiNa) is crucial. This study evaluates the impact of sustainable additives in asphalt mixtures (such as viscosity reducers, encapsulated rejuvenators, reclaimed asphalt pavement (RAP), and banana fibers) on wear layer design using both the empirical DNIT and mechanistic-empirical MeDiNa methodologies. Results indicate that wear layer thickness determined by DNIT is lower compared to the MeDiNa approach. This is evident from the analysis of asphalt mixtures with viscosity reducers and encapsulated rejuvenators, where most exhibit fatigue class zero, leading to thicker pavement layers compared to mixtures classified in fatigue classes 3 and 4. Mixtures incorporating sunflower oil, carnauba wax, canola oil, and beeswax failed to meet MeDiNa’s criteria for permanent deformation under medium traffic, indicating inadequate performance concerning plastic deformation. RAP-added asphalt mixtures predominantly exhibit fatigue classes 3 and 4, except those incorporating cottonseed oil, confirming that oil additions do not benefit asphalt pavement in terms of thickness and fatigue performance. Stone Matrix Asphalt (SMA) mixtures demonstrated superior fatigue resistance, with SMA mixtures containing banana fibers showing the thinnest layers and fatigue classes ranging from 2 to 4. This suggests better performance compared to other types, potentially reducing pavement construction costs.

Aggregates play a crucial role as the structural framework of asphalt mixtures, bearing the majority of the load applied to the pavement. Therefore, it is imperative to thoroughly investigate their characteristics and properties. Understanding the morphological properties of aggregates is particularly significant when considering alternative aggregate materials in asphalt mixtures. This study focuses on a comparative analysis between lateritic and granitic aggregates, both commonly found in Brazil, as constituents of asphalt mixtures. Comprehensive characterization of these aggregates was performed using conventional tests along with the advanced aggregate image measurement system 2 (AIMS2) for imaging. The produced asphalt mixtures underwent various tests, including drainage evaluation, indirect tensile strength measurement, Marshall stability analysis, assessment of moisture susceptibility damage, and Cantabro loss examination. The research revealed that parameters such as surface texture, angularity, porosity, and absorption significantly impact the performance of asphalt mixtures. The mixtures with both evaluated aggregates exhibited values within the specified limits in the standards for each mechanical performance test. While mixtures incorporating lateritic aggregates exhibited superior performance compared to those with granitic aggregates, they demonstrated greater brittleness and sensitivity to moisture due to the inherent porosity, absorption characteristics, and susceptibility to abrasion associated with laterite. Conversely, the utilization of less brittle aggregates necessitates conventional characterization methods, which suffice to comprehend the morphological properties and develop efficient asphalt mixtures.

Reducing dependence on specific types of vegetable oils for Reclaimed Asphalt Pavement (RAP) rejuvenation is critical. Babassu oil, extracted from palm trees, emerges as a promising candidate. This study evaluates the addition of babassu oil to asphalt binder (penetration grade 50/70) in proportions ranging from 1% to 12%. Both direct addition of the oil and incorporation as part of a modified binder in long-term aged binder were tested. A total of 41 samples underwent physical and rheological testing, complemented by aging protocols. The findings indicate that babassu oil significantly decreases binder stiffness, as evidenced by reduced viscosity and performance grade. Samples containing 7% to 12% oil enabled the production of warm mix asphalt at temperatures between 141°C and 150°C. The addition of 3% or more oil mitigated the effects of thermal aging. The oil-modified binder demonstrated superior performance compared to direct oil addition in terms of reducing the stiffness of aged binder. Higher oil contents (greater than 4%) enhanced the interaction, potentially allowing for an increase in RAP content. The integration of babassu oil into asphalt not only improves sustainability but also enhances economic efficiency, thereby supporting the principles of a circular economy.

The role of the adhesion layer on pavements is to guarantee that the structure works as a monolithic system, making it difficult for early cracks to appear due to fatigue or slipping. Thus, this work investigated the factors influencing the adherent behavior between the micro-surfacing and the asphalt concrete. The Leutner shear strengths were analyzed at the interface with bonding paint using the RR-1 C, RR-2 C, and RC1C-E emulsions for three application rates (0.5 l/m², 0.75 l/m², and 1.0 l/m²). Tests were performed at three temperatures (10 °C, 30 °C, and 50 °C). The temperature variable is the main influential factor in the adherent behavior of the asphalt mixtures analyzed. The bonding paint layer increased the shear strength at low temperatures; however, at high temperatures, the bonding layer did not improve adhesion. The RR-2 C type emulsion presented the best performance among those evaluated. The application rate variable was not statistically significant for shear strength. The data indicate that the application of micro-surfacing on asphalt concrete in regions with high temperatures must be performed carefully because, for high temperatures, the technique showed non-adherent behavior.

Incorporating waste into highway construction has shown to be a promising approach for mitigating environmental impacts and reducing production costs by decreasing the consumption of virgin raw materials. In this context, this study investigated the feasibility of using marble and granite industry waste as a partial and total substitute for filler in hot asphalt mixtures. Physical analyses of the constituents were carried out, and the asphalt mixtures were designed using the SUPERPAVE methodology. The filler content obtained was 2 % for the upper gradation curve determined during the dosage process. Subsequently, the marble and granite residue was added in proportions of 50 % and 100 % by weight, replacing the commonly used filler, hydrated lime. The asphalt mixtures were evaluated for their mechanical performance through tests for tensile strength and resilient modulus. The data obtained were subjected to statistical analysis using the Student's t-test with a significance level of 5 %. The results indicated that asphalt mixtures with marble and granite waste exhibited slightly superior mechanical performance compared to the control mixture (with 0 % residue). The statistical test revealed no significant differences between the mixtures for the conducted tests. Additionally, the production costs per ton and per kilometer of highway were practically the same for all three types of evaluated mixtures. In conclusion, the addition of marble and granite industry waste as filler, both partially and entirely, is feasible from both technical and economic perspectives, as it demonstrated equivalent performance to the control mixture. This approach also represents a means to minimize environmental impacts by reducing the demand for raw materials (hydrated lime) and contributing to the proper disposal of waste generated by the ornamental rocks industry.

The pavement industry has been increasingly encouraged to adopt a more circular approach, associating economic development with a more responsible use of natural resources, due to the significant impacts that its activities impose, particularly on the environment and financial resources. One practice aligned with the circular economy trend is the use of Reclaimed Asphalt Pavement (RAP) in asphalt mixtures. Several methods have been adopted to increase the amount of RAP without compromising the mechanical performance of recycled asphalt mixtures, with particular emphasis on warm mix additives and animal and vegetable oils. In this study, the incorporation of zeolite and cottonseed oil in different proportions in these mixtures was evaluated. Blending charts were used to establish the maximum recycling rates based on the critical temperatures of bio-binders formulated with cottonseed oil. For this research, two sets of recycled asphalt mixtures were analyzed: one with 15%, 25%, and 33% RAP, containing 4%, 6%, and 10% cottonseed oil, respectively, and another with 15%, 25%, and 33% RAP, containing 0.3% zeolite. The mixtures were evaluated for both mechanical performance and circularity aspects through an integrated analysis of mechanical properties (tensile strength, resilient modulus, moisture damage, Cantabro abrasion, flow number, fatigue life) and the Mixture Circularity Index (MCIRAM). All recycled mixtures, regardless of the type of additive, demonstrated satisfactory mechanical performance in all tests conducted. The integrated analysis of mechanical and circularity dimensions identified that the recycled asphalt mixture containing 0.3% zeolite and 25% RAP is the most advantageous, as it met the mechanical criteria and exhibited good environmental performance. Among the mixtures with bio-binder, the combination containing 33% RAP and 10% cottonseed oil exhibited superior mechanical performance and demonstrated greater circularity.