Sanja Šurdonja

University of Rijeka · Department of Transportation, Organization and Technology in Construction and Architecture

The reconstruction of a standard at-grade intersection into a roundabout is very often motivated by the need to improve traffic safety, and the effects are usually monitored through before–after analyses based on traffic accidents. As in some countries, like Croatia, data on traffic accidents are not available, in this study, a methodology for the...

The reconstruction of standard at-grade intersection into roundabout is very often motivated by the need to improve the safety of a part of the road network. To assure the effect of the reconstruction before-after analyses based on traffic accidents or some other indirect traffic safety parameter is needed. This paper presents a detailed analysis o...

Excessive and inadequate speeds represent one of the most important causes of traffic accidents, and significantly determine the resulting consequences. The research in this paper refers to the analysis of speeds in one of the important corridors of the main city streets in the city of Rijeka, Croatia. Both streets are approx. 1.5 km long, mostly o...

Intersections are critical points of the urban transport system according to various criteria such as capacity, safety, economic, ecological, etc. The reconstruction of the intersection affects various spatial and traffic aspects. Hence, the effects of the reconstruction need to be analyzed in the planning phase of design and analysis of alternativ...

While roundabouts have been proven to reduce traffic congestion and improve safety, integrating them into a network of signalised intersections can pose challenges for maintaining efficient traffic flow. This preliminary study examines acceptable signalised intersection-roundabout distance using microsimulation analysis. The VISSIM model was design...

The reduction in the traffic death rate in the EU has stagnated in recent years, and the goal of halving the number of fatalities in traffic from 2010 to 2020 has not been met yet. The long-term goal of achieving "Vision 0" requires a multidisciplinary approach and shared responsibility between transport infrastructure that "forgives mistakes", tra...

Roundabouts are very often implemented as a measure for speed control at the intersections where there is a problem with traffic safety. Although the approaching speed is emphasized in some research as relevant for operational speed in the roundabout, there are no detailed analyses of the effects of geometric and traffic elements on approaching spe...

Child pedestrians make up 30% of the total number of children injured in road traffic in the EU. They are a particularly vulnerable subgroup because they exhibit specific traffic behavior related to cognitive and physical development, sociodemographic characteristics, and environmental conditions. This paper provides an overview of research of para...

The safety of pedestrians in the city depends on numerous factors such as crossing habits (traffic behaviour, traffic culture), infrastructural elements and overall traffic conditions. Among the most critical urban areas are those near pedestrian crosswalks with traffic lights. Several studies focus on collecting pedestrian and infrastructure data...

Children pedestrians represent road users with some specifics because of which it is important to study and take into account their traffic behaviour when traffic infrastructure is designed. Design should ensure and enhance their traffic safety because for decades, traffic accidents have been among the first few causes of children and adolescent mo...

Spatial and traffic planning is important in order to achieve a quality, safe, functional, and integrated urban environment. Different tools and expert models were developed that are aimed at a more objective view of the consequences of reconstruction in different spatial and temporal ranges while respecting selection criteria. In this paper we ana...

The process of road network planning and designing in urban areas can be significantly improved by using microsimulation of traffic models. Traffic microsimulations are used for analyses and estimation of new proposals as well as for the reconstruction of existing infrastructure in order to reach optimum solution for defined problem. In this paper,...

Road construction relies on natural material exploitation and it is necessary to find new ways of reducing its negative environmental impact. Simultaneously, number of tyres placed on Croatian (and world) market is constantly growing and the need for waste tyres management will begin to increase due to the wear and tear of tyres in use at the momen...

As urban systems in Europe were mostly designed before the event of cars and then used with them, today general concern about possibility to implement more pedestrian and alternative transport system is highly slowed if not blocked by difficult on site situations that make it problematic to adapt today’s network to more non-only car transport. The...

Children pedestrians make up 30% of the total number of children injured in road traffic in the EU. Research shows that children are injured more often in the urban areas, in residential areas near schools and parks, often at intersections and pedestrian crossings. In this study, children’s traffic behavior was analyzed by observation of signalized...

Modeling the behavior of pedestrians is an important tool in the analysis of their behavior and consequently ensuring the safety of pedestrian traffic. Children pedestrians show specific traffic behavior which is related to cognitive development, and the parameters that affect their traffic behavior are very different. The aim of this paper is to d...

Dvotračna kružna raskrižja primjenjuju se kao rješenje koje povećava kapacitet raskrižja (u usporedbi s klasičnim i jednotračnim kružnim raskrižjem), ali istovremeno značajno smanjuje razinu prometne sigurnosti. Alternativna kružna raskrižja pokazala se kao „kompromis“ između većeg kapaciteta, u odnosu na jednotračna i bolje prometne sigurnosti, u...

Statistical analyses at World level show that traffic accidents are main reasons of death for adolescents and second reason for death of children aged 5 to 14 years. Pedestrian crossings are areas where there is high risk of conflict between pedestrians and vehicles and this is why in this paper research and analyses of children behavior while cros...

The growing need for sustainable mobility has led the transport policy-makers as well as population to use more of soft mobility solutions such as pedestrian and cycling traffic. Several European countries are implementing policies for total mobility with less motorization in order to reduce the negative environmental effects generated by industrie...

The main function of roundabouts is to assure traffic safety and capacity. Operational speed in roundabouts, important for both scopes, is regularly checked in the process of planning and design of roundabouts according to procedures (or models) defined in national technical regulation. There are two mainly used models, one developed in USA and oth...

One of the most common applications of microsimulation traffic modeling is an analysis of the impact of construction or reconstruction of traffic facilities/infrastructure, as well as changes in traffic regulation to the observed traffic network, still in the planning stage. Having in mind that the functioning of the transport system is influenced...

Pavement skid resistance is one of determining road features that contributes to traffic safety. Several influencing factors govern the skid resistance, amongst which the pavement surface texture is the one that could be designed and controlled by the pavement engineers. Pavement surface texture is classified into four categories, where microtextur...

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...

Reconstruction of the intersection on the traffic network is necessary to maintain the required level of traffic safety for all road users, intersection capacity, and the functioning of the intersection in the changed conditions which occur due to, for example, increasing or redistributing traffic or connecting new roads on the network. Before reco...

Field investigations of real-life vehicle paths at single lane rural roundabouts, conducted on a sample of 22 straight directions through roundabouts of varying properties, are presented in this paper. Statistically significant correlations of some roundabout elements and vehicle path radii at roundabout centre were determined and used as a basis f...

Održiva mobilnost ima za cilj osiguravanje mobilnosti, prvenstveno u urbanim područjima, uz istovremeno racionalno korištenje prostora, okoliša i pozitivan utjecaj na zdravlje i općenito kvalitetu života. U ovome radu se prikazuje primjena ovoga koncepta na primjeru manjeg grada, Grada Otočca. Odabrana je uža zona centra Otočca za koju su analizira...

The process of designing roundabouts is an iterative process through which in several checks the design elements of a roundabout get optimized. Existing regulations for roundabouts involves swept path analyses, sight distance analyses and speed analyses of vehicles passing through the roundabout. Speed analyses is done mostly based on two models, D...

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...

urdonja, S., Pranjić, I., Deluka-Tibljaš, A., Renčelj, M.: Sight distance at level crossings and access points: influence of real measured values (input data) to the sight distance calculation Preglednost v nivojskih priključkih in križiš-čih: vpliv realno izmerjenih vrednosti (vhodnih podatkov) na izračun preglednih razdalj Sanja ŠURDONJA, u. d. i...

Maneuvering distance and stopping sight distance are important traffic safety elements at an at-grade intersection. Croatian official standard for sight distance calculation (HRN.U.C4.050) dates from 1990. This regulation treats sight distance values in a very simplified way. The mentioned regulation seems to be outdated since various researches of...

Implementation and reconstruction of urban traffic infrastructure has proved to be very complex task because of different reasons. Among the most important are those connected with negative influence of motorized traffic on urban environment (congestions, safety, environmental problems) and those connected with urban surrounding (lack of free space...

Pavement surface properties measurements are necessary to conduct systematically during the road exploitation in order to ensure the necessary conditions for safe and comfortable driving. Measurement devices from Transportation Laboratory of Faculty of Civil Engineering in Rijeka were used for preliminary investigation of pavement surface friction...

Heat islands are areas that have higher air temperatures than their surroundings. It has been proven that the use of certain types of pavement surface materials contributes to the occurrence of heat islands. The heat island effect is dominant in urban areas, mainly in city centres. To identify potentially favourable pavement surface materials that...

Mikrosimulacijski model proračuna kapaciteta kružnog raskrižja Sažetak Računalni programi namijenjeni prometnim mikrosimulacijama stekli su značajnu popularnost i široku primjenu, kako u praktičnoj primjeni, tako i u istraživanjima. Broj prometnih simulacijskih modela značajno se povećao, a samo do kraja prošloga stoljeća bilo je dostupno više od 5...

Analysis of roundabouts constructed in several Croatian cities has shown that the developed intersection areas, when reconstructing the classical intersections into roundabouts, have limited the outer radius of the intersection as a rule. Croatian guidelines for roundabout design and equipment, for capacity calculation of small and medium roundabou...

Heating pavement or the accumulation of heat in the pavement contributes significantly to the average temperature increase in modern urban environments. Because the portion of traffic areas in city centres is significant, application of pavement structures that reduce the effect of warming is one of the strategies that can help mitigate the urban h...

Today's urban space offers little space for possible traffic solutions of the intersections, especially when it comes to city centres. Possible solutions, which do not require great area, are mini-roundabouts. They are characterized by transit central island, around which passenger vehicles (and other small sizes vehicles) operate as in the other r...

Heat islands are areas in which temperature is higher than that prevailing insurrounding areas. They are dominantly formed in developed urban zones, and arefurther intensified by the use of pavement structures with poor thermal properties. Results obtained during temperature testing conducted on pavements of various types and properties are present...

Heat islands are areas in which temperature is higher than that prevailing in surrounding areas. They are dominantly formed in developed urban zones, and are further intensified by the use of pavement structures with poor thermal properties. Results obtained during temperature testing conducted on pavements of various types and properties are prese...

Today's urban space offers little space for possible traffic solutions of the intersections, especially when it comes to city centres. Possible solutions, which do not require great area, are mini-roundabouts. They are characterized by transit central island, around which passenger vehicles (and other small sizes vehicles) operate as in the other r...

Areas that were once permeable and moist become impermeable and dry because of development of urban areas, and constant construction of city roads and other urban infrastructure. This considerably reduces evaporation, which helps in reducing the air temperature. Complex urban geometry prevents the natural flow of the winds, while the urban canyons...

Like other Croatian cities the city of Rijeka is trying to find optimal traffic solutions for complex problems of growing traffic volumes at existing non-appropriate road network. As a possible solution for the need to increase road and especially intersection capacity and in the same time calm the traffic the idea of reconstruction of the intersec...