Search results for " Ferrovie"
showing 10 items of 383 documents
Ottimizzazione degli aspetti tecnici ed economici nella gestione della sicurezza in galleria
2010
Integrating vehicle specific power methodology and microsimulation in estimating emissions on urban roundabouts
2021
In this study pollutant emissions were estimated from VSP modal emission rates and the distribution of time spent in each VSP mode obtained from the speed profiles both gathered in the field and simulated in AIMSUN at a sample of urban roundabouts. The versatility of the micro-simulation model for a calibration aimed at improving accuracy of emissions estimates was tested in order to ensure that second-by-second trajectories experienced in the field by a test vehicle through the sampled roundabouts properly reflected the simulated speed profiles. The first results which the thesis will refer, confirmed the feasibility of the smart approach that integrates the use of field-observed and simul…
A microsimulation calibration methodology based on speed-density relationships for freeways
2014
This paper describes the calibration methodology based on speed-density relationships in the microsimulation calibration process, stated that they represent the traffic flow phenomenon in a wide range of operational conditions and well summarize all the information that may be collected on field (or following a run of the microsimulation model) on two of the three key variables of traffic flow. The matching of speed-density relationships from field and simulation was evaluated using statistical analysis as technique of pattern recognition. A test freeway segment under uncongested traffic conditions was selected as case study; based on traffic data observed at A22 Brenner Freeway, Italy, sta…
TRATTAMENTO CON CALCE DEI TERRENI ARGILLOSI: STATO ATTUALE DELLA TECNICA
2011
Preliminary Evaluation of Plasmix Compound from Plastics Packaging Waste for Reuse in Bituminous Pavements
2021
Finding an appropriate technical solution for reusing waste plastics is crucial for creating a circular plastic economy. Although mechanical recycling is the best option for recycling post-consumer plastics, some heterogeneous mixed plastics cannot be recycled to produce secondary material due to their very low properties. In this case, alternative routes should be considered in order to limit their disposal as much as possible. Therefore, in order to solve the environmental problems in the landfills of plastic waste recycling, and to improve the mechanical performance of bitumen for road pavement, the reuse of these post-consumer plastic wastes are preliminarily evaluated for the modificat…
Quality-control procedure for dry-process rubberised asphalt mastics
2019
Crumb Rubber (CR) can be incorporated into asphalt mixes via the dry process by directly adding CR into the mixer together with other asphalt mixture’s components, or with the wet process where the CR is used as a bitumen modifier. While the wet process allows an accurate monitoring of the interaction between CR and bitumen, the lack of control represents a main issue in the dry process. In fact, in the latter the CR particles keep swelling during hauling and possibly also after paving operations, often causing workability issues and premature failures. This study wants to provide a methodology that could help quality control procedures of bitumen/filler/rubber systems during mixing, haulin…
Safety evaluation of turbo roundabout with and without internal traffic separations considering autonomous vehicles operation
The paper presents a microsimulation approach for assessing the safety performance of turbo-roundabouts where Cooperative Autonomous Vehicles “CAVs” have been mixed with conventional vehicles “CVs”. Based on the analysis of vehicle trajectories from VISSIM and subsequent analysis of traffic conflicts through the Surrogate Safety Assessment Model (SSAM), the research aims to evaluate the safety benefits of turbo-roundabouts where the lanes are physically separated by raised curbs compared to roundabouts without curbs. The paper shall also lead to describe the methodological path followed to build VISSIM models of turboroundabout with and without raised curbs, to calibrate the simulation mode…
Estimating traffic operations at multi-lane roundabouts: A case study
2014
This paper addresses traffic modeling issues at urban multi-lane roundabouts where, despite circulating vehicles have priority, negotiation of the right-of-way can occur between antagonist traffic flows, as a result of minor drivers’ failing to obey the nominal operating rule (stop or yield control). Existing models for the estimation of operational performances have the shortcoming of not representing the interdependencies between entering and circulating vehicles at multi-lane roundabouts. An analytical capacity model derived from field observations was developed for this kind of intersections in a previous study. The complexity of the model lies in the difficulty of observing the behavio…
LCA of Different Construction Choices for a Double-Track Railway Line for Sustainability Evaluations
2023
The international commitment to achieve carbon neutrality in the next few decades has oriented human activities towards the preservation of natural and non-renewable resources. In this context, a great research effort has been devoted to the search for sustainable solutions for the infrastructure construction sector, based on a thorough assessment of the environmental impact (EI). In this regards, Life Cycle Assessment (LCA) is considered one of the main components of Environmental Impact Assessment (EIA) and, for a comprehensive analysis, all the costs incurred by stakeholders during the useful life of the infrastructure should also be taken into account, applying the Life Cycle Cost (LCC)…
Safety Evaluation of Turbo-Roundabouts with and without Internal Traffic Separations Considering Autonomous Vehicles Operation
2021
The paper presents a microsimulation approach for assessing the safety performance of turbo-roundabouts where Cooperative Autonomous Vehicles “CAVs” have been introduced into the traffic mix alongside conventional vehicles “CVs”. Based on the analysis of vehicle trajectories from VISSIM and subsequent analysis of traffic conflicts through the Surrogate Safety Assessment Model (SSAM), the research aims to evaluate the safety benefits of turbo-roundabouts where the lanes are physically separated by raised curbs, compared to roundabouts without such curbs. The paper will then describe the methodological path followed to build VISSIM models of turbo-roundabouts with and without raised curbs in …