Tullio Giuffrè

Università degli Studi di Enna Kore | Kore Enna · Faculty of Engineering and Architecture

This paper presents a simulation-driven method for assessing the safety and efficiency of traffic at roundabouts incorporating connected and automated vehicle (CAV) technology. Utilizing the newly proposed CAV-based factors specified by the Highway Capacity Manual (HCM) provided a practical framework for analyzing capacity dynamics across various t...

The introduction of connected automated vehicles (CAVs) on freeways raises significant challenges, particularly in interactions with human-driven vehicles, impacting traffic flow and safety. This study employs traffic microsimulation and surrogate safety assessment measures software to delve into CAV–human driver interactions, estimating potential...

Urban mobility underscores the vital importance of ensuring traffic efficiency on road segments, intersections, and transportation networks, especially in challenging circumstances. In this perspective, the essential approach to improving urban intersection efficiency should involve understanding critical factors for maintaining operational perform...

Traffic-calming measures (TCMs) are non-invasive devices designed to improve road mobility and urban areas on a human scale. Despite their potential, they have been in use for a long time and now have to deal with the latest technological innovations in the automotive field, such as cooperative driving technologies (CDTs), to improve energy efficie...

There is increasing interest in connected and automated vehicles (CAVs), since their implementation will transform the nature of transportation and promote social and economic change. Transition toward cooperative driving still requires the understanding of some key questions to assess the performances of CAVs and human-driven vehicles on roundabou...

Connectivity and automation are technologies applied in combination to achieve increases in road safety, traffic efficiency and energy savings. Despite their potential, there are still many open questions regarding how roadway capacitycapacity will be affected and what methods should be employed to assess the expected benefits in the transportation...

Despite the potential of connected and automated vehicles (CAVs), there are still many open questions on how road capacity can be influenced and what methods can be used to assess its expected benefits in the progressive transition towards fully cooperative driving. This paper contributes to a better understanding of the benefits of CAV technologie...

According to international traffic statistics, the quantity of daily traveling vehicles amounts to one billion, and it is estimated that in 2050 that amount will reach four billion. Urban population is growing especially in large metropolitan areas. This increase has different outgrowths concerning regular circulation, safety, and climatic perspect...

In line with globally shared environmental sustainability goals, the shift towards citizen-friendly mobility is changing the way people move through cities and road user behaviour. Building a sustainable road transport requires design knowledge to develop increasingly green road infrastructures and monitoring the environmental impacts from mobile c...

Transformation toward greener, healthier and safer management of urban mobility demand is needed soon. Smart tools are available to assess the impact of new infrastructural projects and road facilities also from an environmental point of view. In this pilot study pollutant emissions at a sample of urban roundabouts were estimated employing the Vehi...

To meet continuous and sustainable improvement on road infrastructures, new technologies and smart devices are encouraging the development of a mobile crowdsensing system for collecting and monitoring data to be used in efficiency assessment. In this view, the paper proposes a methodological approach that employs in an integrated way vehicle trajec...

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 Surro...

The importance of being circular reflects one of the key concepts of the life-cycle thinking that promotes the sustainable production of goods and services. If it is true that the analysis of the product life-cycle is fundamental to optimize the use of resources and to plan for the future reduction of adverse effects on urban environment, it is als...

Generally, during maintenance operations on bridges and motorway viaducts, the circulation of vehicles is limited or suspended. This causes significant economic losses due to the increase in the costs of transport: delays, increased fuel consumption, higher emissions of pollutants into the atmosphere, increased risk of accidents, etc. However, few...

The paper addresses issues related to Passenger Car Equivalents (PCEs) at roundabouts. Compared to other road units, the curvilinear elements of roundabout geometric design may impose greater constraints on vehicular trajectories and have a significant effect on the swept envelope of heavy vehicles. Specifically, the aim of the paper is to present...

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 roundab...

Sustainable management of urban areas is becoming during the last decades, one of the most important challenges of the 21st century that resulted in the concept of “smart city“. The city can be defined as "smart" when social capital, traditional and modern (ICT) communication infrastructure encourage sustainable economic development and high qualit...

Tunnels are a critical component of transportation infrastructure, but they are vulnerable to severe environmental conditions, accidental blast events as well as some structural damages coming from design or construction errors. Under these circumstances, they require repair and maintenance activities for which tunnels must be closed to traffic and...

Maintenance of bridge decks is an issue that Italy feels very strongly nowadays. High performances mortars are often used, especially during the extraordinary maintenance, in order to improve the structural performance of the decks but, the change of their mechanical properties caused by vehicular-induced vibrations has been little studied till now...

Passenger Car Equivalents (PCEs in the following) are used to transform a mixed fleet of vehicles into a fleet of equivalent passenger cars and to analyze capacity and level-of-service of roads and intersections. Most roundabouts guidelines propose constant values for PCEs but a single PCE value can result improper under heterogeneous traffic condi...

This paper addresses issues on road safety analysis through microscopic traffic simulation models. The Surrogate Safety Assessment Model (SSAM) was applied to read vehicle trajectory files generated by two micro-simulators and then calculate surrogate measures of safety. Since safety assessment of any road entity can provide different results based...

The paper presents a microsimulation-based approach for roundabout safety performance evaluation. Based on a sample of Slovenian roundabouts, the vehicle trajectories exported from AIMSUN and VISSIM were used to estimate traffic conflicts using the Surrogate Safety Assessment Model (SSAM). AIMSUN and VISSIM were calibrated for single-lane, double-l...

In the last forty, years semi-flexible pavements have been successfully employed, especially in those areas subjected to heavy and slow-moving loads. They usually comprise a wearing course of Grouted Macadam, a composite pavement material that provides significant advantages in comparison to both concrete and asphalt pavements. On the other hand, t...

Driving experiences provided by the introduction of new vehicle technologies are directly impacting the criteria for road network design. New criteria should be taken into consideration by designers, researchers and car owners in order to assure traffic safety in changed conditions that will appear with, for example, introduction of Autonomous Vehi...

Nowadays, one important challenge is to demonstrate an innovative and integrated approach for the sustainable construction of roads considering the whole life cycle of the infrastructure. Road pavements with multiple asphalt layers generally undergo prolonged environmental exposure and the alternation between solar irradiation and low temperatures....

“Standard” roundabouts, for example those designed in some European countries, can often be characterized by low levels of safety or capacity and a high degree of sustainability. Given the proliferation of newer layouts, it is of interest to explore whether design practices could be improved by capitalizing on the experience gained internationally....

Road safety is a major issue in a number of countries around the world. Advanced technologies are in place to reduce the road hazards. These technologies include the overall automated vehicles (AV) as a part of an intelligent transportation system. They are a type of active safety systems. This paper highlights the working mechanism, advantages an...

The use of the lightened embankment is, nowadays, turning out to be a solution widely adopted for the fast rebuilding of roads or where the bearing capacity of the foundation soil does not allow the construction of embankment using the classic methods. The stress-strain response when the asphalt layers are confined below by a high insulation materi...

Background: Smart mobility can contribute to the design of “Smart cities” to answer users’ requests in terms of transport network efficiency, environmental and social sustainability. Focusing on urban smart mobility issues, the most important aspects are the presence of a connected transportation system, the availability of its information in the a...

Within the category of vulnerable road users pedestrian are recognised as those with the highest probability in road accidents to be affected by serious or fatal casualties. However, due to the randomness of their behaviour and sometimes the limited attention of traffic light operation settings devote to this road user category, in particular in is...

In the last few years a considerable amount of safety models and evaluation tasks have been developed and specifically dedicated to roundabouts. Several safety performance functions (SPFs), indeed, have been implemented for roundabouts worldwide. Since SPFs are developed using crashes, traffic volume and other characteristics of a specific site (or...

Energy management policy is an important part of the environmental and climate change policies and permits to reach the goals of improved security of energy supply, economic efficiency and of greenhouse gases emissions reduction. In these years, the use of market mechanisms to meet environmental objectives is really growing, with the most important...

In the paper, a choice criterion between flower roundabouts and double-lane roundabouts is proposed, focusing on operational benefits that can derive from one scheme over the other, and outlining a general framework for benefit-cost analysis. In order to assess operational benefits of innovative roundabouts over modern roundabouts, a comparative an...

In recent years, Wireless Sensor Networks (WSN) have been increasingly involved in Intelligent Transportation System (ITS) optimization, especially in dynamic management of signalized intersections. This paper discusses the state of art and shows an IEEE 802.15.4 network architecture to monitor vehicular traffic flows near to a traffic light. The a...

Starting from consideration that urban intersections are sites with promise for safety and operational improvements, the paper describes the steps taken to develop a crash predictive model for estimating the safety performance of urban unsignalized intersections located in Palermo, Italy. The focus is on unsignalized four-legged one-way intersectio...

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 operationa...

According to the state-of-the-art of the methodologies, the development of safety performance functions (SPFs) for road sections and intersections requires the employment of statistical models to predict expected crash frequencies on the basis of traffic volumes and site characteristics to be surveyed and used as input to models. Nevertheless, lite...

In statistical analysis of crash count data, as well as in estimating Safety Performance Functions (SPFs), the failure of Poisson equidispersion hypothesis and the temporal correlation in annual crash counts must be considered to improve the reliability of estimation of the parameters. After a short discussion on the statistical tools accounting fo...

Parking is becoming an expensive resource in almost any major city in the world, and its limited availability is a concurrent cause of urban traffic congestion, and air pollution. In old cities, the structure of the public parking space is rigidly organised and often in the form of on-street public parking spots. Unfortunately, these public parking...

Parking is becoming an expensive resource in almost any major city in the world. Current technically advanced solutions for parking management are concerned with the application of secured wireless network and sensor communication for parking reservation. Moreover new rules concerning financial transactions in mobile payment allow the definition of...

Airports need to find a way to overcome economic, financial and infrastructural problems in a coherent attempt of definition of a conceptual framework of the airport business as a whole. In this context, an increasing relevance has the model of Multi-Airport System (MAS).The research uses case study analysis approach. More in details, business and...

Previous research, based on potential conflicts analysis, has provided a quantitative evaluation of 'proneness' to red-light running (RLR) behaviour at urban signalised intersections (Giuffrè & Rinelli, 2006) varying geometric, traffic flow and driver characteristics. Recent study (Bell, Galatioto, Giuffrè, & Tesoriere, 2012) demonstrated the poten...

Building on previous research a conceptual framework, based on potential conflicts analysis, has provided a quantitative evaluation of 'proneness' to red-light running behaviour at urban signalised intersections of different geometric, flow and driver characteristics. The results provided evidence that commonly used violation rates could cause inap...

This article summarizes a research program designed to assess operating conditions through capacity estimation at not-conventional roundabouts characterized by a central island with a large diameter and by two (or more) entering and circulating lanes. Although giving priority to vehicles on circulatory roadway is the nominal operating rule, on-fiel...

Polluting emissions depend on vehicle characteristics and on traffic conditions expected after the construction of a road project. Nevertheless, in the assessment of new projects, the task of road designer becomes uncertain when the reduction in polluting emissions has to be evaluated. Moreover, vehicle emissions are highly linked to modal vehicle...

Based on previous potential conflicts analysis studies and recent research from the authors [1], this paper address the need to demonstrate the transferability of a new modelling approach by testing the model using a 4 arms signalised junction in Enna (Italy), where an extensive period of continuous video recording has been carried out. Different c...

Traffic calming schemes refer to a combination of road network planning and engineering measures to minimize undesirable effects of traffic in residential areas. The traffic calming role in urban road network management is, indeed, to enhance road safety as well as other aspects of liveability for the citizens; in this context accident reduction ca...

The role of traffic calming schemes in urban network management is mainly to minimize the undesirable effect of traffic in residential areas; in this context accident reduction can be a realistic objective. Several studies, indeed, inform us that traffic calming is a major part of the treatments available to reduce road accidents in urban areas. Pa...

The inapplicability of current methods for analyzing the operations of notconventional urban roundabouts (i.e. not referable to standard schemes) seriously hampers the assessment of their operational performances. Moreover, local constraints and the road network structure have produced lots of geometric layouts that make it hard to propose a framew...

Traffic calming schemes refer to a combination of road network planning and engineering measures to minimize undesirable effects of traffic in residential areas. The traffic calming role in urban road network management is, indeed, to enhance road safety as well as other aspects of liveability for the citizens; in this context accident reduction ca...

Calibrating a safety performance function (SPF) with many years of accident data creates a temporal correlation that traditional model calibration procedures cannot deal with. It is well known that generalized estimating equations (GEE) models are able to incorporate trends into accident data and thus overcome difficulties in accounting for correla...

Evaluation of proneness to red light running behavior, because it results from human and road factors, can aid in a proper selection of the sites to be treated and thereby increase the benefit of countermeasures to reduce the red light running (RLR) phenomenon. Starting from the conceptual framework of a model based on potential conflicts analysis,...

Evaluation of proneness to red light running behavior, because it results from human and road factors, can aid in a proper selection of the sites to be treated and thereby increase the benefit of countermeasures to reduce the red light running (RLR) phenomenon. Starting from the conceptual framework of a model based on potential conflicts analysis,...

The roundabout installations in urban areas are often conditioned by the existing constraints of different kind (particularly physical and topographical ones), compelling road engineers to make "compromise solutions" compared with the traditional geometric design standards of roundabouts; operational performances and risk conditions, in their turn,...