Search results for "ferrovie"
showing 10 items of 384 documents
SUP R DSS: A sustainability-based decision support & system for road pavements
2019
Road pavement community members are increasingly becoming aware of the need to incorporating the principles of sustainable development into the sector. Policies are also going in this direction and as a consequence in the recent years researchers and practitioners are coming up with new materials, technologies and practices designed to reduce the negative impacts of their activities in the surroundings. Within this framework the road pavements sector is witnessing a paradigm shift towards the development of pavement technologies incorporating high-content of recycled materials, as well as best practices to decrease the overall carbon footprint. These are all promising solutions that to the …
Design considerations of high RAP-content asphalt produced at reduced temperatures
2018
In many countries recycling of reclaimed asphalt pavement (RAP) for road surface layers is limited to a maximum of 10–30%. This is due to technical limitation of common asphalt plant but also to specifications that are still restrictive when it comes to increasing RAP in surface courses. The mistrust in this practice is mainly related to uncertainty in performance of these mixes as well as to existing fundamental issues with the mix design, especially when production temperatures are lowered. This paper analyses some of the factors affecting the design of warm asphalt mixtures for surface course layers containing 50% RAP, and suggests a framework to justify the common assumption of full ble…
Photogrammetric UAV technologies aimed at monitoring of infrastructures
2022
The research has three key concept: the first one is the application of data analysis using limited data sets to understand historical and future road maintenance interventions; the second one is the application of image based 3D modelling and analysis of pavement distresses; the third one is the application of deep learning to detect and pinpoint pavement distresses
Impacts of roundabouts in suburban areas on congestion-specific vehicle speed profiles, pollutant and noise emissions: an empirical analysis
2019
Abstract Increasing concern about global warming and air quality has meant an increasing use of energetic and environmental indicators in roundabout design. This research compares different suburban roundabouts in terms of traffic performance, pollutant and noise emissions through an integrated empirical assessment. Field measurements were carried out with a light duty vehicle in single-lane (SL), compact two-lane (CTL) and multi-lane (ML) roundabouts using Portable Emission Measurements Systems, On-Board Diagnostic scan tool and Sound Level Meter, to measure real-world exhaust emissions, engine activity and acoustic data, respectively. Afterwards, predictive discrete choice models that cor…
Modello fuzzy di calcolo della distanza di visibilità per il sorpasso su strade extraurbane ad unica carreggiata bidirezionale
2002
Lo studio di modelli teorici che ben rappresentino, nella loro articolazione, le manovre di guida in sede stradale è da sempre un esercizio tanto praticato quanto complesso. La difficoltà di delineare compiutamente tali manovre, di definirne l’interazione cinematica dei veicoli coinvolti è comprovata dalla varietà di modelli presenti in letteratura. Con il presente lavoro ci si propone di pervenire alla formulazione di un modello originale di calcolo della distanza di visibilità per il sorpasso su strade bidirezionali ad unica carreggiata, il quale tenga debitamente conto del coacervo delle variabili cinematiche, meccaniche, geometriche, ambientali e di traffico, così come del comportamento…
Studio di conglomerati bituminosi con granulato di gomma proveniente da pneumatici dismessi
2002
La ricerca di conglomerati bituminosi di elevate prestazioni sovente si associa allo studio delle implicazioni ambientali che la produzione, la posa in opera e l’esercizio di tali materiali comportano. Un aspetto assai importante, in tal senso, è l’opportunità che alcune modalità produttive offrono in termini di un ridotto consumo di inerti e del contestuale impiego di materiali destinati a discarica che, invece, vengono inseriti in processi di riciclaggio. È questo il caso della gomma proveniente dal riciclaggio industriale di pneumatici dismessi che, negli Stati Uniti ed in Canada, è divenuta una fonte sostanziosa per la realizzazione di conglomerati bituminosi. La presente ricerca, dopo …
Asphalt mixtures improved with plastic additives: mix design and case study in an airport
La crescente domanda di prestazioni e le esigenze di salvaguardia dell’ecosistema spingono a sviluppare nuove tecnologie di lavorazione, a sperimentare l’impiego di nuovi materiali, a migliorare i metodi di progetto delle miscele. Il criterio seguito è quello di un impiego più razionale delle risorse e dell’utilizzo di tecniche a basso impatto ambientale. Per ragioni tecniche ed economiche stiamo assistendo al fenomeno di espansione nel mercato degli additivi, impiegati nella produzione di miscele bituminose per migliorarne le prestazioni e ridurre i costi. In generale, però riuscire a soddisfare tutti gli obiettivi con un unico prodotto è difficile, perché l’alta qualità richiede costi più…
EMISSION FACTORS, VEHICLE MODAL ACTIVITY AND ROAD OPERATIONS. A MESOSCOPIC APPROACH
2009
Current studies underline that vehicle emissions are highly linked to modal vehicle activity and a modal approach to traffic-related air quality modeling is suitable to estimate mobile source contribution to air quality. Pollutant emissions depend on characteristics of vehicles in traffic flow and on road operating conditions predictable after the implementation of the road project; then, the usual emission rate models do not predict properly the on-road vehicles emissions of modal traffic events, such as those ones occurring at intersections. Moreover modal activity analysis carried out at micro scale level, as required by modal emission models, will be still necessary to value reliable em…
Life cycle assessment of low temperature asphalt mixtures for road pavement surfaces: A comparative analysis
2018
The increasing fuel consumption demand, the accelerated pressure imposed by the depletion of 5 scarce raw materials and the urgent environmental protection requirements are forcing the change of 6 pavement industry and academia community’s research endeavors towards the development of low 7 emissions road paving technologies able to significantly reduce mixing and compaction temperature as 8 well as the consumption of virgin raw materials. One set of relatively recent technologies in the field of 9 pavement materials that aims at addressing those concerns are the warm mix asphalt (WMA). In fact, 10 they have the potential to allow the reduction of energy consumption and airborne emissions d…
A systematic assessment of road pavement sustainability through a review of rating tools
2017
Pavements are engineered systems present in every modern society, and they have significant environmental, economic and social impacts. In an effort to promote more sustainable decisions regarding pavement design, construction and management, several pavement sustainability assessment tools have been developed. This research reviewed some of these tools and found that many of them do not treat the pavement as a system; instead, they seek to optimize individual aspects of the pavement in an effort to increase its sustainability. Therefore, a framework for analytically assessing the system outcomes towards sustainable objectives is presented and applied for modern pavement sustainability asse…