From Traditional to Electrified Urban Road Networks: The Integration of Fuzzy Analytic Hierarchy Process and GIS as a Tool to Define a Feasibility Index—An Italian Case Study

To achieve sustainable development in the road sector, the use of Electric Vehicles (EVs) appears as a positive response to transport emissions. Among the available technologies, dynamic charging seems to overcome the main weakness points of EVs, even if it requires that traditional roads (t-roads) be equipped with a system providing electricity for EVs. Thus, so-called electrified roads (e-roads) must be implemented into the urban road networks. Since it is not possible to electrify all roads simultaneously, and also to consider the demand needs of citizens, a selection criterion is essential. This research describes and develops a simple, self-explanatory, repeatable, and adaptable selection criterion aimed at helping city managers in prioritizing the roads of an urban network to be upgraded from t-road to e-road status. This method belongs to the so-called Multicriteria Spatial Decision Support Systems (MC SDSS)—processes useful for solving spatial problems through the integration of multicriteria analysis (Fuzzy Analytic Hierarchy Process, F-AHP) with a geo referenced data management and analysis tool (GIS). The developed algorithm is based on several criteria related to the infrastructure/transport, social and environmental areas. The result of the implemented method is a Feasibility Index (FI), able to prioritize the roads most eligible to be upgraded as e-roads, as also verified by its application on the urban area of Milan (Italy)

Assessing the Impact of Rutting Depth of Bituminous Airport Runway Pavements on Aircraft Landing Braking Distance during Intense Precipitation

A runway pavement during its useful life is subject to a series of deteriorations because of repeated load cycles and environmental conditions. One of the most common deteriorations is the formation of rutting (surface depression in the wheel path) on the runway surface. Rutting negatively affects aircraft performance during landings and will behave even worse during precipitation or with the existence of fluid contaminations on the surface. This paper aims to develop a model for calculating aircraft braking distance during landing on wet-pavement runways affected by rutting based on dynamic skid resistances generated by tire–fluid–pavement interactions. Intense precipitation, variable rutting depths for a 100 m length step, water film depths (e.g., 1 to 26 mm), and aircraft wheel loads (e.g., 10 to 140 kN) are considered as the boundary conditions of the developed model. The output is a model that can estimate aircraft braking distance as a function of rutting depth and can perform further assessment of the probability of the occurrence of landing overrun. After validating the model with existing methodologies and calibrating it according to the actual landing distance required for each type of aircraft, an Italian airport is simulated using a model with real data regarding the level of service of its pavement surface characteristics

Influence of Embedded Charging Units Characteristics on Long-Term Structural Behavior of E-Roads

The use of Electric Vehicles (EV) seems to be a promising solution to achieve a sustainable road transport system. Among the contactless dynamic vehicle charging technologies, the use of Charging Units (CUs)—cement concrete box—embedded into the road pavement seems to be a favorable option. The available scientific papers related to the structural effects of embedding CUs in road pavements consider the CU as a solid box, even if a cavity is needed for the electrical technologies’ accommodation. This is why the current research is aimed at studying electrified roads (e-road) with different CU cavity shapes and dimensions. In detail, pavement structural responses are investigated, as a first step, adopting a Finite Element Model (FEM), and, as a second step, the long-term performances (fatigue cracking/rutting proneness) are evaluated. The study is divided into two phases: the theoretical fatigue/rutting assessment, which allows to calculate the critical load repetitions leading to pavement failure, and an urban case study with the goals of both assessing the theoretical results and computing fatigue/rutting performance with real scale traffic conditions. The outcomes demonstrate that CUs can be used with no significant impacts on the long-term road pavement structural performance, laying the foundation for a future upgrading of the existing urban road networks

Deterioration trends of asphalt pavement friction and roughness from medium-term surveys on major Italian roads

Deterioration models are the key factor for effective Pavement Management Systems, helping out road agencies to assess the actual pavement condition and forecast future performance of the asset. Among pavement condition characteristics, friction should be taken into account due to its important effect on user safety, while roughness could be used to express user comfort. The purpose of this study was to provide a reasonable case study for future improvements of Italian road management, even if the length of the analyzed highways was not intended to be representative of the overall Italian network.This research studied the friction trend (Side Force Coefficient) depending on traffic levels (ESALs) and pavement aging for Italian highways, combining the data with roughness and macrotexture. Surface characteristics were monitored during a seven-year time span. A selection of different road sections with homogeneous traffic levels, similar environmental conditions and surface material was performed and high-speed/high-quality road surveys were used for distress data collection. Pavement deterioration models for Italian road sectors were developed at project level, as starting point to advance pavement management practices in Italy. Degradation curves showed the same trends for similar pavement structures, materials and traffic levels; on the other hand, differences in pavement characteristics, increased ESALs and various maintenance treatments significantly altered those trends. Keywords: Pavement Management System, Deterioration models, Friction, Roughness, MPD, High-speed monitorin

Assessment of fatigue resistance of additivated asphalt concrete incorporating fibers and polymers

This paper reports the evaluation of fatigue response of asphalt mixtures produced with different additives, namely cellulose and synthetic fibers, amorphous polyolefin, Ethyl Vinyl Acetate (EVA) in comparison with conventional asphalt mixtures. The additive content was also analyzed by producing asphalt mixtures with 3, 6 and 9% of additive. Fatigue testing was performed with an indirect tensile test apparatus under controlled stress mode of loading. A comparing analysis of the fatigue resistance within different methods was carried out. Fatigue life was defined using the classical approach in which the number of cycles reaches the double of initial deformation. It was also defined in terms of different methods based on dissipated energy: total dissipated energy, ratio of dissipated energy change and plateau value. This paper offers an analysis of different methods of evaluating the indirect tensile fatigue test. The testing conducted clearly shows that polymer modification may extend the fatigue life and that energetic methods can be effectively applied to data from indirect tensile fatigue tests

Effect of recycled concrete aggregate features on adhesion properties of asphalt mortar-aggregate interface

Asphalt-aggregate interface’s adhesion properties commonly affect the damage initiation and evolution within asphalt concrete materials, related to pavement durability and quality. The scope of this research was to investigate the influence of Recycled Concrete Aggregate (RCA) features on asphalt mortar-aggregate interface adhesion. Firstly, a three-dimensional reconstruction model of RCA was carried out using X-ray CT tomography and digital image processing. In this regard, five feature indicators, namely cement mortar content, sphericity, flat and elongated ratio, angularity, and surface texture, were proposed. Based on a bilinear cohesive zone model, the interface damage behavior of asphalt mortar-RCA was investigated by using a uniaxial compression simu- lation. Finally, a GA-BP artificial neural network was conducted to predict and quantify the effect of each feature indicator of RCA on interface adhesion. The results showed that when RCA had lower cement mortar content, higher sphericity value, and smoother surface, the asphalt mortar-RCA system was less prone to interface adhesion failure. The 5-14-1 GA-BP artificial neural network proposed in this study showed very good perfor- mance in predicting the interfacial dissipation damage energy with a mean-squared error value of 3.52 × 10^-4 for testing dataset. The cement mortar content parameter exhibited a remarkable influence on the interface adhesion property, and its global contribution to the interfacial dissipation damage energy (0.3486) was more than twice that of the surface texture parameter (0.1316). In future studies, the performance characteristics of cement mortar can be further investigated, thereby proposing RCA’s performance optimization technology

Sovrastrutture ferroviarie per alta velocita': sviluppo di una metodologia di calcolo ed analisi teorico-sperimentale sul subballast per il miglioramento delle prestazioni

Dottorato di ricerca in ingegneria dei trasporti. 8. ciclo. Coordinatore O. Pavese. Tutore P. GiannattasioConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal