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Transport engineers, authorities, companies, stakeholders, and all experts involved on transportation planning work every day to improve the trip experience of people, and to reduce the impacts on the collectivity. Traffic congestion, pollution and energy consumption are core problems for the transportation system. On the one hand a congested road causes an exponential increase in the energy consumption and waiting times, while a not-congested road can be more attractive and slowly become congested over time; on the other hand, the environmental capacity of road links is not perceived, thus generating high emission and distribution of pollutants. In fact, the ability of transportation planners is to avoid traffic congestion but offer at the same time pleasant, accessible and sustainable trips. This may include several planning techniques which may involve traffic calming and limitations, lane reservation, changing in the road network and geometry, as well as apply new technologies, services and means of transportation. It is worth noting that trying these features directly on a city can be very expensive and produce irreparable damages to the transportation system; also, traditional transport models are not able to adeguately simulate most of these features. Recently, it has been recently introduced the digital twin, a digital reproduction of a city to be used as a test platform for ’what if’ scenarios. In fact, transport digital twin is not just a digital reproduction of the transportation system, but consider reaction of humans to the changes applied to the system, in order to make a comparison between different scenarios. The present document studies large-scale digital twins, which are able to consider the spatial propagation of effects, and particularly focuses on advanced and time-dependent models able to simulate the door-to-door trip experience of all users and adequately model the transport features of the future.

Socio-technical systems have very complex structure in which multidimensional co-evolutionary dynamics between people and technical factors are presented. Each urban zone has different socio-technical conditions in which the built environment and the user choices are varied. Understanding how urban transportation is shaped by socio-technical factors and how these factors in turn affect the transportation users and the transportation performance worldwide is important in order to support sustainable transportation planning. An integrative literature review and multiple worldwide analysis of transport indicators conducted in the present thesis. Approximately two hundred cities distributed over sixty countries were examined. The present worldwide transport analysis contains socio-information of the population, the working population, the annual growth rate, the income level, the car ownership, the higher education level, and the culture dimensions. On top of that, the analysis contains technical information of the population density, the land area, infrastructure accessibility and infrastructure design parameters. User preferences were assessed through urban travel mode share. Furthermore, in order to assess the transport performance, specific data were used for the analysis such as congestion level, commute distance by modes, transport-related energy consumption and transport-related CO2 emissions of cities. The present thesis aimed to provide a holistic view of socio-technical factors shaping urban transportation for transport planners and local governments. The thesis focused on understanding which alternative transport modes can be sustainable under specific socio-technical conditions and how to attract travellers towards these sustainable modes. The thesis also assessed, under which technical conditions an urban transport system can minimize its socio-economic costs and environmental impacts. Furthermore, interrelations among the socio-technical factors, their inf

Nell’analisi del deflusso autostradale trovano ampia applicazione le metodologie HCM e molti paesi, tra cui l’Italia, fanno ad esse riferimento per la valutazione delle infrastrutture esistenti e di progetto. Le norme italiane, pur citando il manuale, non esplicitano chiaramente riferimenti o procedure. Le esperienze delle Concessionarie autostradali, inoltre, mostrano dubbi sulla rappresentatività dei risultati ottenuti applicando le procedure americane, evidenziando un divario tra gli output e la percezione del reale grado di congestione. Considerando alcuni tratti autostradali italiani, la ricerca si propone di verificare l’applicabilità di procedure per la calibrazione del Diagramma Fondamentale del traffico e per la valutazione della qualità del deflusso, testando la consistenza dei risultati con gli output delle metodologie HCM2010. Rispetto agli andamenti standard, i Diagrammi ottenuti mostrano una migliore capacità di interpretare i dati sperimentali, in considerazione delle condizioni specifiche delle sezioni, delle differenze nelle caratteristiche dei veicoli o nel comportamento e nelle regole di guida. In questi termini, i modelli calibrati stimano valori di flusso e densità critici inferiori a quelli HCM2010, ma prossimi a quelli suggeriti dall’analogo manuale tedesco HBS. L'analisi comparativa, a valle della quale sono approfondite e motivate le principali differenze tra il contesto italiano, quello americano e altre situazioni internazionali, mostra come il manuale statunitense tenda ad esprimere condizioni di circolazione migliori di quelle sintetizzate con i modelli calibrati. La ricerca evidenzia, quindi, la possibilità di una sottostima della congestione sulle sezioni in esame, suggerendo un cauto e attento utilizzo delle procedure standard. I risultati ottenuti rilevano, in generale, come il mancato utilizzo di modelli calibrati e l'uso alternativo di procedure che appaiono troppo generali e provenienti da contesti eterogenei possa condizionare e, HCM methodologies are widely used for analyzing freeways. Many countries, including Italy, refers to HCM for the assessment of existing or planned infrastructures. Although citing the manual, the Italian regulations don't make explicit references or procedures. Furthermore, the experiences of motorway operators show doubts about the representativeness of the results obtained by the American procedures, showing a gap between the output and the perception of the real level of congestion. Considering some Italian motorway sections, this research aims to analyze the applicability of a procedure for the calibration of the Fundamental Diagram of traffic flows and for the assessment of the quality of service, testing the consistency of the results with the output of HCM2010 methodologies. In comparison to standards, the calibrated Diagrams show a better match with data, due to the special conditions of the sections, the differences in vehicle characteristics or behavior and driving rules. In this way, the calibrated models estimate critical flow and density values lower than those of HCM2010, but close to the similar German manual HBS. The comparative analysis, after which the main differences between the Italian context, the American and other international situations are studied in deep and further motivated, shows as the US manual tends to give better traffic flow conditions (i.e. less congestion) than those synthesized using the calibrated models. The research remarks, therefore, the possibility of an underestimation of the congestion on the sections examined, suggesting a cautious and careful use of standard procedures. Failure to use calibrated procedures and models and the alternative use of procedures which seem too general and coming from heterogeneous contexts may affect and penalize the reliability of the results. This can result in an incoherent representation of congestion levels and may invalidate the requirements of adequacy and representativeness in the eva

In recent years the availability of GPS data has seen as a significant improvement in data accuracy, continuity and quality, due to the spread of smartphones and mobile applications for self-localization and navigation. GPS datasets provide analysts with geo-referenced information about users’ mobility and habits. The first part of the thesis consisted of an analysis of the context of bicycle facilities for the city of Bologna, Italy, made through experimental measures of cycleway and road usage rates, and cycling speed. The following part of the study focused on the use of GPS traces datasets, which allow to record a wide amount of bike trips. The main advances in the last years’ relevant literature have been described. Subsequently, two case studies have been analyzed: GPS traces datasets recorded through mobile devices, both for the city of Bologna and for the whole Netherlands. First, the original dataset of GPS points have been properly filtered in order to exclude instrumental errors. The GPS points have then been matched to a high-detail network database, in order to obtain the actual routes chosen by cyclists. The considered road networks included both attributes of the roadway and attributes of the bicycle facilities, when existing. The percentage of the trips done on a bicycle facility versus the roadway could thus be compared with the results from the first part of the study, and be used as a measure of the attractiveness and effectiveness of the bicycle facilities available. Furthermore, the chosen routes could be compared with the shortest routes for each origin-destination pair, and route choice models could be calibrated, based on different relevant attributes of the networks, of users, and of trips.