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In recent years, Building Information Modeling (BIM) tools have increased the productivity of infrastructure projects through more efficient information management and by fostering communication between different actors in the process [1,2,3]. At the same time, the growing need to introduce sustainability indicators, calculated through the life cycle assessment (LCA) methodology, has prompted an increase in the amount of data to be managed throughout the life cycle of an infrastructure project [4,5]. The present work consists of developing a BIM-based LCA tool aimed at the calculation of several environmental indicators through the informative content of a road pavement BIM; the tool is specifically designed to avoid errors in LCA calculations during the early design stages, reduce the engineer’s effort through automation and support sustainable decision making in the infrastructure domain. An LCA-based pavement information model was developed by defining and adding several customized property sets, respectively, containing the specific road pavement materials‘ features and some selected environmental impact categories; a bidirectional information exchange path was established between BIM and the LCA tool to automate the LCA calculations and dynamically update the mentioned environmental indicators’ property sets, whenever the geometry of the pavement and the asphalt materials’ features change. The developed tool allows one to practically integrate pavement-related environmental sustainability requirements into BIM projects, with specific reference to asphalt pavement solutions that apply circular economy principles (i.e., secondary raw materials and cold recycling technologies), in light of more environmentally friendly pavement construction practices.

The continuous growth of waste is generating worldwide more and more increasing related environmental concerns. Anything that is not recycled or recuperated from waste represents a loss of raw materials and other production factors used in the manufacture, transport and consumer phases of the product. This research explored the potential of three waste namely Construction and Demolition (CD) waste, Fly Ash (FA), and Jet Grouting (JG) waste as fillers in comparison to the traditional limestone one for making hot asphalt mastics for road pavement, through a rheological analysis and environmental compatibility tests towards the release of potentially toxic elements. A total of eight asphalt mastics were prepared by using two filler-to-binder weight ratios (f/b) of 0.5 and 1 for blending each filler with a neat bitumen 50/70 penetration grade. The Frequency Sweep test and the Multiple Stress Creep and Recovery (MSCR) test were carried out to investigate the rheological properties of the asphalt mastics. Asphalt mastics containing FA and JG fillers were found to be more mechanically and environmentally efficient than traditional limestone mastic in particular by adopting an f/b equal to 1 where it was observed higher complex shear modulus values, G*, (on average 50% compared to the traditional asphalt mastic) and lower non-recoverable creep compliance values, Jnr, (on average 35% compared to the traditional asphalt mastic) at all test temperatures investigated. Based on the suggested ranking methodology, CD emerged as the filler performing in the same way of the traditional one. All the waste containing mastics, showed up noticeable environmental compatibility, being the potentially toxic elements completely immobilized into the mastics’ structure e practically not releasable into acidic water, highlighting the waste recycling for road pavements as primary strategy to immobilize hazardous wastes.

The latest advancements in road asphalt materials and construction technologies have increased the difficulty for engineers to select the appropriate pavement design solution with consideration of life cycle assessment (LCA) methodology. On the other hand, infrastructure building information modeling (BIM) tools allow practitioners to efficiently store and manage large amounts of data, supporting decision making in road asphalt pavement design and management. This research contributes to setting up a dynamic LCA tool for the specific evaluation of designed road asphalt pavement solutions involving alternative materials and advanced recycling technologies; the tool is structured to minimize the need of input data by the designer, that are usually unknown during the early design stage, and automate the entire LCA calculation process to reduce the designer efforts and avoid any errors during data transcription. A traditional BIM workflow was integrated with additional user-defined property sets to simultaneously compute the environmental impact of the entire life cycle of the asphalt pavement, and dynamically update the result basing on the design thickness of the pavement layers, the specific features of materials and an external database of several life cycle impact category indicators that can be edited and updated gradually during more advanced design stage. The proposed BIM-LCA aims to be a practical and dynamic way to integrate environmental considerations into road pavement design, encouraging the use of digital tools in road industry and ultimately supporting a pavement maintenance decision-making process oriented toward circular economy.

The use of building information modeling (BIM) for infrastructures is on the rise but the use of the life cycle cost analysis (LCCA) integrated within the BIM environment itself to analyze multiple design alternatives and set up a proper maintenance plan has not yet been developed. It is possible to integrate evaluation of maintenance and waste recovery strategies, minimizing costs and the use of raw materials. A visual programming tool was exploited to set up an application that applies the LCCA methodology to a road pavement project in the early design phase, returning the total maintenance cost updated to the year of construction, the number of maintenance interventions, and the residual value of accumulated fatigue damage. The execution of the LCCA tool dynamically updates the properties of the BIM model with the resulting pavement management plan and returns multiple outputs, giving to the user the possibility of making further assessments and store the data as needed. The developed application shows that BIM is a promising tool to implement more complex and useful analyses that can reduce the maintenance planning time and allow the designer to choose between multiple alternative solutions already in the early design phase, bringing consistent cost savings through the possibility of finding the minimum cost solution based on the specific project needs in compliance with the quality and safety criteria to be guaranteed for the road category.

The circular economy aims to change the paradigm in relation to the linear economy by limiting the environmental impact and waste of resources, as well as increasing efficiency at all stages of the product economy; the recent warnings about waste pollution and the limits of natural resources are encouraging its development. The purpose of this research is to investigate the potential environmental and mechanical benefits of reusing two different waste, namely jet grouting waste (JGW) and plastic waste (PW) for producing hot asphalt mastics made up of bitumen and filler: the JGW comes from the soil consolidation activities during pavement construction, while the PW, a mixture of high-density polyethylene, low density polyethylene, polypropylene and polyethylene terephthalate derives from a plastic recycling plant. First, three mastics engineered by keeping constant viscosity and a filler over bitumen ratio of 0.3 for the asphalt mastic with limestone filler (LM), 0.29 for the mastic with JGW (JGWM) and 0.1 for the solution containing PW (PWM), were investigated through a dynamic shear rheometer to explore their rheological behavior. Second main step concerned the life cycle assessment (LCA) of the three asphalt mastics that, in turn, are included into the base layer of a flexible road pavement by following ReCiPe impact assessment methodology. Primary results in terms of mechanical performance demonstrated that: 1) JGWM outperformed LM in terms of complex shear modulus, which resulted 19% higher than that of LM in the temperature range below 30 °C, and 2) PWM returned on average 30% lower non-recoverable creep compliance at 50 °C under 0.1 and 3.2 kPa than remaining solutions under analysis. LCA outcomes showed, on the one hand, that PWM had the best environmental performance, expressing the lowest damage to human health, ecosystems and resource availability indicators, returning on average 34% and 19% lower indicators than LM and JGWM, respectively. On the other hand, JGWM still represented an overall improvement of the environmental performance compared to LM, returning the best performance in terms of damage to human health, which lowers by 23%, due to the reduction of the output waste stream.

The growing number of vehicles is related to the overall growth in the consumption of fuel from fossil fuels or electricity, so new ways are being sought to increase the efficiency of propulsion or the recovery of energy from driving. This article deals with the possibility of recovering kinetic energy from the movement of vehicles, specifically from the air flowing around a passing car. The subject of measurements and simulations were parameters influencing the amount of recovered energy such as the location of the wind turbine near the road, its distance from the side of the moving vehicle, turbine height from the road, speed and size of the vehicle front (car, bus, truck). The measured values were compared with the values from the simulations performed in the program Fluent, and it was shown that in passenger cars the highest air flow is 0.5–1 m above the road and the closest possible to vehicles. With regard to feasibility, the smallest distance was considered to be 0.5 m from the side of the vehicle. Measurements in real traffic showed delay of the air flow behind the vehicle by 1.5–3 s depending on the size of the vehicle and the need for sufficient traffic density. The high intensity of vehicles in urban and suburban areas predestines them to deploy this system. Conversely, in rail transport, given the low frequency of vehicles, the use of this system is unjustified.

In order to meet the environmental needs caused by large plastic waste accumulation, in the road construction sector, an effort is being made to integrate plastic waste with the function of polymer into asphalt mixtures; with the purpose of improving the mechanical performance of the pavement layers. This study focuses on the effect of a recycled mixture of plastic waste on the chemical, thermal, and rheological properties of designed asphalt blends and on the identification of the most suitable composition blend to be proposed for making asphalt mixture through a dry modification method. Thermo-gravimetric analysis, differential scanning calorimetry, and Fourier transform infrared spectroscopy analysis were carried out to investigate the effect of various concentrations and dimensions of plastic waste (PW) on the neat binder (NB). The frequency sweep test and the multiple stress creep and recovery test were performed to analyze the viscoelastic behavior of the asphalt blends made up of PW in comparison with NB and a commercial modified bitumen (MB). It has been observed that the presence of various types of plastic materials having different melting temperatures does not allow a total melting of PW powder at the mixing temperatures. However, the addition of PW in the asphalt blend significantly improved the aging resistance without affecting the oxidation process of the plastic compound present in the asphalt blend. Furthermore, when the asphalt blend mixed with 20% PW by the weight of bitumen is adopted into the asphalt mixture as polymer, it improves the elasticity and strengthens the mixture better than the mixture containing MB.

Due to the introduction of secondary materials, the asphalt mixtures to be designed and tested in our laboratories are constantly becoming much more complex than traditional asphalt mixtures making difficult to use conventional laboratory procedure and/or predict expected results. This study proposes a comprehensive characterization of asphalt mixture modified with recycled polymer compound by using both wet and dry process proposing adjustments to laboratory mixing and sample compaction procedure. Accordingly, three AC20 Hot Asphalt Mixture (HMA) were designed and their conventional and performance related properties were assessed by looking at a) Indirect Tensile test (ITS) a) moisture damage by Indirect Tensile strength Ratio (ITSR) test; b) cracking by fatigue and Semi-Circular Bending tests and c) rutting both considering Stiffness Modulus (ITSM) and susceptibility to deform by Wheel Tracker. The results demonstrate that the addition of recycled polymer compounds using dry process might lead to the need to adaptation of the laboratory mixing procedure and the proposed mixing and compaction procedures allowed to engineer a superior recycled polymer modified asphalt mixture manufactured through the dry process, since an increment of mechanical related properties, than traditional asphalt solutions, was exhibited by these modified asphalt mixtures in terms of ITS (+32%), ITSM (11% at 10 degrees C, +18% at 20 degrees C, and +34% at 40 degrees C), rutting resistance (rut depth of 1.86 mm vs 1.92 mm) and fatigue life.