Search results for " Ferrovie"
showing 10 items of 383 documents
Stima dei costi della sicurezza nei cantieri: ancora troppe incertezze
2009
Estimation of Passenger Car Equivalents for single-lane roundabouts using a microsimulation-based procedure
2017
Calibration of microscopic traffic simulation models for single-lane roundabouts.Use of a meta-analytical estimation of critical and follow up headways.Use of a genetic algorithm-based procedure.Calculation of passenger car equivalents for single-lane roundabouts. Passenger car equivalents for heavy vehicles are required to carry out capacity calculations and perform operational analysis of any road entity (roadway segments or intersections). At single-lane roundabouts, the constraints to the vehicular trajectories imposed by the curvilinear geometric design and the driver's gap acceptance behaviour are expected to produce an impact of the heavy vehicles on the quality of traffic flow diffe…
Estimating pollutant emissions based on speed profiles at urban roundabouts: A pilot study
2019
The paper describes the pilot study conducted to assess the feasibility of the empirical approach utilizing vehicle trajectory data from a smartphone app and the Vehicle-Specific Power methodology to estimate pollutant emissions at urban roundabouts. The goal of this research phase is to acquire instantaneous speed data from a sample of six roundabouts located in the road network of the City of Palermo, Italy, and quantify emissions generated by the test vehicle through the examined roundabouts. For the case studies of roundabouts acceleration events in the circulating and exiting areas contributed to about 25% of the emissions for a given speed profile. More in general, the results from th…
A model for evaluating the environmental and functional benefits of “innovative” roundabouts
2015
This study looks at the singling out of a multi-parameter criterion for choosing conventional or innovative roundabout layouts, by taking functional, environmental and economic aspects into consideration. The performances of three conventional roundabouts (with different lane number at entries and through the ring), turbo-roundabouts and roundabouts with right-turn bypass lane on all the arms (flower roundabouts) have been compared in terms of vehicle delays and pollutant (carbon dioxide, nitrogen oxides, particle pollution (PM10 and PM2.5)) emissions. By means of closed-form capacity models and with the help of COPERT IV© software, several traffic simulations have been carried out, referre…
Can crumb rubber modifier effectively replace the use of polymer- modified bitumen in asphalt mixture?
2021
Laboratory scale mechanical performances on six plant produced mixtures; three semi-dense surface courses and three dense binder courses modified with engineered crumb rubber (ECR) using the dry process are presented. The two types of mixtures produced and investigated fulfilled for the most part, the requirements of the Swiss and/or US standards regarding volumetric properties, water sensitivity and rutting. In advanced testing where no requirements exist, the dense ECR mixtures performed similar to the reference polymer modified mixtures and slightly worse for semi-dense mixtures in high temperature tests, where the binder becomes viscous in the rubber-binder composite and its ability to …
Road Safety in Brief
2019
Road safety issue has been the subject of study for many years and with each passing day transportation engineering expands this research area since it is a social matter of absolute priority.
Pavement life cycle management: Towards a sustainability assessment framework in Europe
2020
Pavement Life Cycle Management is a 2-year international project aiming at supporting European National Road Authorities (NRAs) to introduce sustainability in their practices by providing training on Life Cycle techniques and a user-friendly package to support their widespread implementation. The first task in Pavement Life Cycle Management (Pave-mentLCM) project is the creation of a Sustainability Assessment (SA) framework that complies with EN15643-5 and consequently include the three pillars of sustainability, use a life cycle ap-proach and use quantifiable sustainability performance indicators. This paper presents the first steps towards the creation of the framework which includes the …
L' EVOLUZIONE DEL CONCETTO DI SICUREZZA NELLA GESTIONE DELLA RETE FERROVIARIA
2011
Le procedure di audit della sicurezza sul progetto e sulle infrastrutture in esercizio
2010
Approccio teorico-sperimentale per l'analisi delle condizioni operative di rotatorie urbane non convenzionali
2008
I metodi tradizionali di analisi delle rotatorie cadono in difetto in presenza di schemi organizzativi dell’intersezione, nei quali l’organizzazione geometrica, unitamente alla molteplicità delle situazioni di traffico ed all’inserimento in contesti vincolati, induce comportamenti di guida anche molto distanti da quelli osservabili in rotatorie convenzionali. Quanto evidenziato interessa, in particolare, l’ambito urbano, dove le intersezioni a circolazione rotatoria risultano particolarmente diffuse e si caratterizzano per requisiti geometrico-funzionali spesso distanti da quelli propri delle rotatorie convenzionali. Uno dei maggiori ostacoli che si incontrano nell’analisi delle condizioni …