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Apart from the pressing problems of global warming due to outputs of atmospheric gases, the global society is increasingly troubled by the tasks of managing solid waste. In this regard, innovative solutions have been advanced for the reuse of solid waste in non-traditional sectors, including in road asphalt production. The present study investigates the potential production of sustainable superior-performing asphalt mastics (neat bitumen and filler), in which the filler is obtained through procedures of reusing shredded waste plastic (WP) and jet grouting waste (JGW) recovered from soil consolidation activities, rather than traditional limestone filler. A first phase of the study involved the production and the comparison of three asphalt mastics: a mastic containing JGW (JGWM) with a filler over bitumen ratio (f/b) of 0.29, a limestone mastic (LM) blended with an f/b ratio of 0.30 and a mastic containing WP (WPM) made up with an f/b ratio of 0.10. The mechanical characterization was carried out by use of a dynamic shear rheometer for analysis of the rheological performance of the three mastics in terms of rigidity, elasticity and resistance to permanent deformation. A life cycle assessment was conducted using the eighteen impact category indicators of the ReCiPe method, as a means of determining the human and environmental benefits of the innovative hot asphalt mastics. The main results from the mechanical point of view were that, compared to traditional LM: a) at temperatures from 0 to 30 °C, the use of JGW achieved an average 30% greater stiffness; b) at 40 and 50 °C, the WPM reduced permanent deformation by 56%. The most significant outcomes of the environmental analysis were: a) the use of JGWM achieved lower terrestrial ecotoxicity and freshwater eutrophication, respectively 53% and up to 97% less than with LM; b) the WPM achieved 33% and 38% reductions in effects on global warming and fossil resource scarcity, respectively.

This study defined the mechanical/volumetric properties and the environmental compatibility of bituminous mixtures containing fly ashes as alternative of traditional limestone filler. The research study is articulated in different steps as follows: a) characterization of fly ashes according to UNI EN 1303 Standard; b) environmental compatibility analysis of mastics containing fly ashes by using a leaching test; c) stiffness evaluation of the mastics containing limestone and fly ash filler by static testing, as Delta Ring and Ball Test, and dynamic testing, as Frequency Sweep Test; d) mechanical and volumetric characterization of asphalt concrete containing fly ashes and limestone filler starting from a phase of mix design of hot mix asphalt mixtures. The characteristics of rigidity of the bituminous conglomerates has been evaluated using the HMA optimal mixture analysis through a dynamic test with a sinusoidal load. Then, the ability of two different HMA to endure a permanent deformation was evaluated by a Repeated Load Axial Test. The results has shown that mixtures of Hot Mix Asphalt with flying ashes as filler, compared to Hot Mix Asphalt containing limestone filler, is preferred in terms of mechanical performances and relevant environmental compatibility evaluated with a leaching test.

The study aimed to compare mechanical and environmental performance of four solutions for base layer of a flexible pavement with hot and cold technology, with and without the reemployment of jet grouting waste obtained from land consolidation work during the construction of underground tunnels. The laboratory investigation provided cold bituminous mixture with optimum performance mechanical compared to hot bituminous mixtures. The environmental evaluation has been focused on Life Cycle Assessment (LCA) taking into account all manufacturing process from cradle to laying of flexible pavement having as base layer the four mixtures investigated.

The research program aims to define a new methodological procedure to design eco-friendly modified asphalt using PMA methodology in substitution to PMB technology. In the starting phase two different mixes were optimized using SUPERPAVE methodology, and the ITS value was evaluated. The first mixture is a Traditional Mixture (TM) and another one is an Modified Mixture (MM) with the addition of 5% (by total mass of bitumen) of polymeric compound using PMA technology. From the ITS analysis, the modified mixture shows an ITS value higher about of 20% than traditional Hot Mix Asphalt.

inter-laboratory experiments were designed to evaluate the impact of plas- tic waste blended directly in bitumen and to assess the properties, using conventional and advanced bituminous binder testing. The blends tar- geted 5% of plastic waste in 95% bitumen, using two types of polyethy- lene (PE) primary (pellets) and secondary (shreds) waste. The experiments showed that the addition of PE waste to bitumen does not alter the chem- istry of the bitumen, the blending is physical. The DSR results indicate a strong dependency on the testing temperature as at low temperatures the composite material bitumen and PE behave both elastically whereas, at higher temperatures, the bitumen becomes viscoelastic. The MSCR tests indicated that the neat binder is more sensitive to permanent deformation compared to the blends with PE. The fatigue performance using the Linear Amplitude Sweep test showed a better performance in terms of stress and fatigue life for the PE blends.

The transition from Building Information Modelling (BIM) to Heritage Building Information Modelling (H-BIM) is intended to pursue an adequate knowledge of the artefact that is to be preserved, progressively replacing the traditional methods of restoration and structural reinforcement projects with new tools for the management of both existing information and new interventions. The aim of the paper is to show the application of the H-BIM method to a stone pavement road located in the Archaeological Site of Pompeii. In detail, starting from a laser scanner-based survey, juxtaposed with coordinated points georeferenced through a total station, point clouds were handled by means of several BIM-based tools to perform the road design process, starting from the digital elevation model (DEM) and proceeding to the corridor representation. Subsequently, a visual programming application based on Python language was adopted to update the corridor information by means of the object property set. As preliminary results, a tool, complete with graphical and non-graphical information, is proposed to be used in conservation, maintenance and restoration projects.

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 research focuses on Indirect Tensile Strength variation by changing Height and Diameter of bituminous specimens related to AC16 dense-graded binder course with limestone aggregates and neat bitumen at 4.5% following SUPERPAVE procedure. 70 specimens were prepared by using gyratory compactor by fixing hmin/D ratio equals 0.68. A total of 20 specimens whose diameter is 100 mm were prepared and the other 50 specimens were made according to a 150 mm diameter. Then, 30 of 50 specimens with a 150 mm diameter were cut in two different ways: 10 specimens were cut from the centerline and 20 specimens were cut both from the bottom and upper part to obtain a final height falling a range of 35 and 75 mm in compliance with UNIEN12697-23. Then second step refers to H0 hypothesis test as follows: could ITS values resulting from specimens prepared with 150 mm in diameter and cut by using different procedures be equal to ITS values (mean 3.47 MPa) of specimens prepared with 100 mm in diameter and different height (mean height 69.5 mm) with a significance level of 0.05? The results showed that no statistical difference exists between the 100 mm in diameter specimens and 150 mm in diameter specimens that were cut both from the upper and bottom part. However, in the other scenarios statistical differences were founded. Overall, according to the results it can be concluded that 100 mm in diameter specimens can be used for ITS evaluation of AC specimens instead of 150 mm, which consequently resulted in less materials and simplified lab-scale asphalt manufacturing procedures.

Great efforts have been made in recent years to improve the mechanical properties of asphalt mixtures by replacing conventional mix components with innovative ones or by adding materials such as polymers. Hence, the innovative-sustainable road materials to be investigated through laboratory tests require articulated procedures, the research here presented aims to provide an experimental-methodological approach to analyse the mechanical performance of untraditional hot asphalt mixtures made up using a polymer compound of recycled plastics. Three Asphalt Concrete 20 (AC20) Hot Asphalt Mixtures (HMA) were analysed by measuring base properties (i.e., indirect tensile strength and moisture damage) and advanced features (i.e., stiffness, fatigue, cracking and rutting resistance). As a result, the addition of polymer compound using dry process might lead firstly to change the laboratory mixing procedure than the traditional hot limestone asphalt solutions. The main benefits derived from the adoption of this innovative technology compared to the conventional ones are as follows: a) an improvement of resistance to moisture damage (at 15 °C); b) a suitable stiffness at 10, 20 and 40 °C; c) an increment of the cracking resistance (at 10 °C) and d) a good rutting resistance in terms of rut depth (at 60 °C). .

Road maintenance operations involve the preservation of the optimal functionality of the pavement. Sometimes the rehabilitation of the pavement layout does not have long lasting effects due to a lack of compliance with the constraints imposed by the technical specifications for the design of materials. The purpose of this paper is to present an efficient BIM tool to help in road maintenance operations through the management of data arising from laboratory testing of road pavement bituminous materials required for the quality control of mixtures. The database associated to the BIM model is a collection of three years of data derived from laboratory investigation on bituminous mixtures’ samples adopted for the maintenance of four main roads located in southern Italy. An algorithm that interacts with the three-dimensional road model has been implemented in order to give road administrations an easy-to-read alert signal for the road pavement structure of the road network that may present the most critical conditions due to poor mechanical and physical features.

As a response to the “end of waste” strategy, this study focuses on an innovative laboratory-methodological approach to carrying out measurements for multi-scale characterization of road pavements construction materials; specifically, the engineering performance of sustainable hot asphalt mastics made up using plastic waste as filler was measured to gain a deeper understanding of the physico-machanical performance of traditional and modern mastics, which seriouly affect the design and durability of the final whole road asphalt pavement. Asphalt mastics are bitumen-based materials that give cohesion to the whole asphalt mixture. They consist of filler (with a passing by mass percentage ranging from 70 to 100 for a sieve size of 0.063 mm) and bitumen. Nine asphalt solutions prepared using three percentages of filler content (10, 15, and 20%) by the total weight of neat bitumen whose weight was kept constant were investigated. Firstly, for plastic waste particles, the maximum melting temperature was examined using Differential Scanning Calorimetry, and the phase transitions were subjected to thermogravimetric analysis. The morphology of all the asphalt solutions was then observed using Scanning Electron Microscope, while the advanced rheological properties were measured by means of a Dynamic Shear Rheometer. Cluster Analysis and Principal Component Analysis were performed to aggregate solutions with similar performance within the same group, and, secondly, to provide a small number of uncorrelated explanatory laboratory variables. Three clusters and three Principle Components were found to be perfectly interconnected to describe asphalt mastics performance.

Building information modeling (BIM) is a powerful methodological approach for designers that has revolutionized the field of architecture and construction for some years now, minimizing errors and making the entire design, construction, and management process more efficient. The first results have been so encouraging that many countries, from Europe to the United States to Asian countries, have adopted specific regulations to promote its development and use. BIM models are based on the Industry Foundation Classes (IFC) standard, i.e., an object-based file format with a data model developed by building SMART to facilitate interoperability. Objects are characterized by properties, such as geometry, material, cost, and all related construction process information, such as scheduling or the maintenance process. The 3D modeling of these objects geometric information is parametric, in order to make the design more flexible. This research work offers an insight into the possibilities offered by different BIM-based tools for parametric modeling applied in the railway sector whereby an example of a railway section model is presented. Indeed, the focus will be on the creation of parametric objects representing railway components, as existing BIM object libraries lack them in the IFC2 × 3 standard format.

The use of reclaimed asphalt pavement is a practice that is adding significant environmental value to road technologies, not only due to the reduction of materials sent to landfill but also because of the mechanical properties of the reclaimed asphalt (RA) that can be reused. This research focuses on the rheological properties of hot and cold bituminous mastics made up as follows: (1) hot mastics mixed with limestone filler (LF) and bitumen, (2) hot mastics, made from bitumen mixed with jet grouting waste (JW), a mixture of water, cement, and soil derived from land consolidation work in underground tunnels, and (3) hot mastics mixed with LF and JW as filler and bitumen. Three different ratios (0.3, 0.4, and 0.5) of filler per unit of neat bitumen (B50/70) were studied. The same number was used for mixing cold mastics, by using an appropriate laboratory protocol designed since the adoption of a cationic bituminous emulsion. A total of 18 mastics were prepared and investigated. The comparison was carried out using the frequency sweep (FS) test, analysing shear modulus G∗, applying the multistress creep and recovery (MSCR) test (40°C and 60°C) as well as the delta ring and ball (ΔR&B) test, focusing on two main issues: (1) the stiffening effect caused by the filler type used for mixing each mastic, and (2) a comparison, in terms of stiffening effects and nonrecoverable creep compliance (Jnr) of hot and cold mastic performance to highlight JW reuse in mastics. The results showed that the best G∗ performance at test temperatures higher than 30°C is given by cold mastic after 28 days of curing time when JW is added to LF and bitumen. The lowest Jnr value was 40°C and 60°C for the same mastic.

Although building information modeling (BIM) has been widely adopted in the building industry for several decades, the use of BIM in the context of transportation infrastructure has been slow in terms of both adoption and application. Industry and academia are increasingly making efforts to adopt BIM for other non-building civil infrastructure but, so far, there has not been a comprehensive review of these efforts specifically regarding transportation. This paper explores BIM implementation in an infrastructure design project. An Autodesk &reg, BIM-based tool, Civil 3D, is proposed as a potential BIM tool platform. This paper also focuses on modeling specific road elements not editable from the standard library, such as guardrails and retaining walls, as well as proposing different solutions using Revit and Subassembly Composer and analyzing the interoperability among BIM-based tools.

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.

The large amount of plastic waste is currently causing serious pollution to the environment mainly due to long decomposition times and their dispersion. In order to avoid that the pollution by plastics could worsen further, it is trying to encourage companies to recycle existing pallets to create new products. This study investigates the volumetric and mechanical properties of hot bituminous mastics made up using plastic waste materials (PW) as filler. The PW has a maximum size of 2 mm and a melting temperature between 120 and 260 °C. Scanning Electron Microscopy of the PW reveals a mesh structure of elongate elements marked by a much rougher surface than traditional limestone filler (LF). The first step of the study focused primarily on searching for the optimal blending time for the mastics; a total of nine mastics were made up, and no substantial differences were found for any of them on increasing mixing time from 10 up to 60 min in terms of softening point, penetration at 25 °C or dynamic viscosity at 100 °C. Thus, a period of 10 min was selected for mixing all the mastics. The second step focused on the investigation of rheological properties using a dynamic shear rheometer and carrying out a Frequency Sweep (FS) test at temperatures ranging from 0 °C to 50 °C with increments of 10 °C, and a Multiple Stress Creep and Recovery (MSCR) test under 0.1 and 3.2 kPa load levels at temperatures of 40 and 50 °C. The two resulting best solutions are made up of a) 20% PW (HP02), and b) 5% LF plus 15% PW (HLP02), both by the total weight of B5070. Specifically, the shear modulus G* for mastics containing PW showed a distinct increase in G* compared both with B5070 and traditional mastics made up of LF; in particular, the gap becomes more marked moving towards 50 °C, where the best performance of HP02 is obtained. Moving on to illustrate the main results of the MSCR analysis, it was observed that the HP02 and HLP02 solutions showed good recoverable deformation already from the end of the loading phase without waiting for the last step of the unloading cycles at two test temperatures and under two stress levels.