Search

Traffic volumes in road traffic show growth, especially in developed countries. Where necessary and depending on space, financial possibilities and other aspects, increasingly more capacity roads (multi-lane highways, complex grade-separated interchange, etc.) are being built. The places, where the roads meet (i.e. at the intersections), are the most problematic (traffic accidents, capacity problems, etc.). Standard intersections (i.e. level intersections, roundabouts, intersections with traffic lights or grade-separated interchanges) do not fulfill their task. Traffic designers, in collaboration with traffic engineers, therefore design non-standard types of intersections, which are basically combinations of standard ones. For example, turbo-roundabouts, roundabouts with traffic lights, double roundabouts, and multiple roundabouts, are created. The paper deals with the roundabouts with traffic lights. This type is not common intersection type in the Czech Republic. On the other hand, for example in Holland, it is quite common to meet a turbo roundabout with traffic lights. Some of them are very complicated - for example, with seven traffic lanes on one entrance to the intersection. However, despite their complexity, the traffic on them is smooth. The paper describes the roundabouts with traffic lights from a safety point of view (analysis of conflict situations) and from a capacity point of view. [ABSTRACT FROM AUTHOR]

The problem of intersection capacity is a constantly discussed topic in the field of traffic engineering. Uncontrolled intersections have the lowest capacity, roundabouts and controlled intersections follow, and grade-separated interchanges have the highest capacity. However, in many cases, a grade-separated interchange cannot be built (mainly for spatial or financial reasons). In these cases, it is necessary to look for solutions to increase the capacity of other types of intersections. The paper deals with capacity assessment of controlled intersections with traffic lights and with U-turn maneuver. The U-turn is a maneuver of a 180° rotation to reverse the direction of travel. The name of this maneuver is derived from the letter U because this maneuver looks like it. The U-turn maneuver is also possible on divided roads (by special U-turn ramps), but this paper does not deal with it. In some countries, the U-turn is illegal (especially for the intersections with traffic lights). An example of such a country is for example the Czech Republic. On the other hand, some countries are allowed this maneuver (for example Poland). The paper compares the results of capacity assessment of intersections with and without U-turn maneuver for Czech conditions. There are used the qualitative methods based on Germany methodology HBS. These methods are based on the traffic volumes on entries and they deal with numbers of traffic lanes, time spaces, average delay times and level of service for entries. [ABSTRACT FROM AUTHOR]

The paper deals with comparison of selected capacity calculations for roundabouts used in the Czech Republic. Some traffic engineers use the qualitative methods based on Germany methodology HBS, but some ones still use the quantitative methods for capacity assessment of roundabouts. The quantitative methods are based on the traffic volumes on entries and circulatory roadway of roundabout and they usually use an array of coefficients which represent next roundabout parameters. The qualitative methods are also based on the traffic volumes on entries and circulatory roadway of roundabout and they minutely deal with numbers of traffic lanes, time spaces and mainly average delay times (e.g. critical gap and follow-time) and level of service for entries. The method used in the Czech Republic also deals with the capacity of the exits, including influence of pedestrians on pedestrian crossings and volume/capacity ratio for exits. Attention is also paid to the other types of roundabouts, i.e. not only single-lane and double-lane roundabouts, but also mini and turbo roundabouts. This paper presents the results of calculations by both types of methods for various types of roundabouts and shows the differences used methods. [ABSTRACT FROM AUTHOR]

The paper deals with the analysis of the design elements of the road at the crossing point of the railway line. For the analysis were selected existing level crossings in the Czech Republic, where problems were found during the traffic. These were mainly problems of repeated disorder road pavement in contact with the construction of the level crossing. In addition, there are problems with the crossing of motor road transport or freight traffic. Particularly in the case of longer vehicles (heavy goods vehicles, public transport vehicles or long-distance transport), occurred there was contact between the vehicle chassis and the level crossing structure. For some level crossings, the vehicle has been get stuck at the level crossing. These level crossings, including the roads, were focused and further analysed in terms of design elements (track alignment and vertical design elements and their mutual combination). This paper describes the results that were found, and highlights the mistakes that were made in the design. It also highlights the importance of a correct proposal for road communication at the crossing point of the railway, particularly for road and rail safety reasons. [ABSTRACT FROM AUTHOR]

The paper deals with the influence of mining works on the transport in the area mainly the structural layers of transport-related engineering structures elements as railways, roads, railway crossings and the overall transport system. Long-term underground coal mining is usually associated with environmental impacts in the Moravian-Silesian Region in the Czech Republic. There are two types of undermined areas in mentioned region: District of Ostrava where the mines were closed and the mining phenomena are considered terminated, and District of Karvina where coal is still mined and the impacts of mining are still present. With the extraction downturn, the sources and objectives of transport have changed including the characteristics of transport flows of all traffic roads and connections. Thus, in this area it is necessary to identify the consequences of mining, reclaim the landscape, reconstruct civil structures and ensure safe and reliable transport. This paper describes the defects of objects which are related with traffic infrastructure, for example drop of the railway crossing structure, road defects, rail track defects, increased wear sleepers due to frequent manipulations when repairing the geometric position of the track etc. [ABSTRACT FROM AUTHOR]

The cycle transport is fast developing in the Czech Republic. Gradually becomes not only a sport and way for use free time, but also a full-fledged type of transport. For this to become cycling transport alternative to mobility in cities is need to urban development must also adapt to the needs of cycle transport. It is not only the development of cycle track, but also integrating of cycling transport into the transport system. For fluent and particularly safe keeping cycle transport is also used by interchanges. The paper deals with the design a cycling track, which passes through the branch interchanges. When designing the cycling track has been used for reasons of safety interchanges with use filled spandrel bridge structure. The paper describes the issue of foundation steel structures, including its connection to the retaining wall that carries the load from the roadway. In conclusion are mentions advantages and disadvantages of the use of steel structures for routing cycling transport. [ABSTRACT FROM AUTHOR]

Roundabouts are generally perceived as safe solution of dangerous intersections. If they are built correctly, number of traffic accidents is lower than in case of common intersection types - it relates also to severity of results (i.e. fewer deaths and serious injuries, and lower property damages). In comparison with uncontrolled intersections the roundabouts have higher capacity available. Czech standards and technical conditions assess roundabout capacity on the basis of calculation of capacity for approaches and departures. Both cases take geometric parameters of roundabout, number of traffic lanes, traffic volumes etc. into account. Besides, capacity calculation of departures from roundabout takes account of occurrence of pedestrians on pedestrian crossings. Influence of possible cycle pass (i.e. occurrence of passing cyclists) isn't solved here. One of reasons is the fact that the cyclists must yield to vehicles in the Czech Republic. This paper deals with possibility of change when conversely the vehicles must yield to cyclists on cycle pass (like in some foreign countries) in Czech conditions (i.e. with using Czech standards and technical conditions). This change will certainly influence road traffic and decreases roundabout departure capacity. The paper describes two method of capacity assessment: numerical method according to Czech technical conditions and assessment by micro simulation models made in PTV VISSIM software. [ABSTRACT FROM AUTHOR]

In the Czech Republic there is a dramatic deterioration in the construction condition of the culverts. This development was signed by defects caused mainly by traffic from overloaded vehicles, traffic growth, atmospheric effects, chemical effects caused by salting in the winter time, construction type of culverts and age of culverts. One of the most important factors is insufficient pursuance of evidence culverts and construction maintenance, e.g. remove defects occurring in the beginning. The paper deals with disorder problems of culverts and problems of their maintenance on roads of the Czech Republic. The paper introduction describes the different type of culverts in terms of the use of construction material and the type of support structure. Furthermore, the paper presents the most common defects structural and technical condition of the culvert and the influences of disorders on the structural condition. The paper describes the issue of evidence of culverts and assessment of construction and technical condition. The paper conclusion mentions proposals for measures to increase of the reliability and safety. [ABSTRACT FROM AUTHOR]

During mining activities the constructions on the surface are usually influenced. Extent and time course of negative influences is dependent on array of geological, hydro geological and mining conditions and last not least also on the way of implementation of line construction (i.e. how it is ready to react to these awaited influences). In the past for that reason the array of calculation methods working with more or less precision with using for prognosis of influence of mining activities (i.e. influence of mining subsidence) were evolved. These methods were based on level measuring of constructions and monitoring and disposal their failures. At present the precision of these calculation methods is about ± 20 %. The paper deals primary with failures of culverts which are caused by influence of terrain deformation as effect of mining activities - drop, horizontal movement, rotation and curvature of the terrain, and horizontal strain (i.e. stretching or compressing). For these reasons the vertical alignment of culvert is damaged, the entrance or outlet of culvert become clogged and a lot of failures which limit function of culverts are detected. Dysfunctional culvert might negative effect on earth construction and other objects of substructure of line constructions - it may endanger safety and reliability of traffic on road or railroads. For these reasons it is necessary to apply the principles for security of construction for awaited influences of mining subsidence, i.e. the design of the substructure must respect used material to preserve the stable deformation during swamping or lifting by water. [ABSTRACT FROM AUTHOR]

The article deals with the various type of the roads construction, which are located in industrial areas and therefore are burdened by traffic of heavy vehicles. Article at its beginning analyzes problems of pavement design and regulations, according to which the construction of various roads are designed. There is also mention of the existence of an internal regulation, which sets individual roads composition in industrial areas. Details of all faults on access road to the industrial area, are described in detail. Material for construction of this is leftover material from reconstruction of the blast furnaces - cold dump. The article also focuses on failures the cobbled cover of paved area in the industrial zone, which is used for transshipment of cargo. Particular there is analyze of compaction of the road foundation and also ensure of water drainage. There are two variants of possible solution described in detail water drainage. The article also describes the design of reconstruction of road surfacing near the fire station, where combined various types of road construction. At the end of this article there is a summary of the issues with the design of road burden by the heavy trucks traffic. [ABSTRACT FROM AUTHOR]

Turbo-roundabouts are becoming a new type of intersections realized in the Czech Republic. Turbo-roundabout is roundabout with special arrangement of two or more lanes, which should ensure greater security and traffic capacity than conventional roundabouts with two or more lanes. This article presents different types of turboroundabouts. Physical separation of lanes of the circulatory roadway in the area of turbo-roundabouts and in the area of their individual types is an often discussed problem. The article focuses closely on the use of physical separation between traffic lanes and describes use of different types of materials and executions that are realized at turbo-roundabouts in European countries. Further, there are also described types of separation of lanes at intersections which have already been implemented in the Czech Republic. The article also deals with road safety according to the number of conflict points at individual types of roundabouts, with the influence of the physical separation of lanes, with the execution of road marking and with water runoff. In conclusion is also mentioned the maintenance of intersections during the winter months. [ABSTRACT FROM AUTHOR]

The article presents the results of research on traffic safety on roundabouts in the Czech Republic. The project, entitled "The Impact of the Geometry of Construction Elements on Road Traffic Safety and Fluency on Roundabouts and the Possibility of Accidents Prediction" was carried out by VŠB-Technical University of Ostrava over the years 2009 and 2010. The results have shown that two factors have had a major impact on safety, namely the number of lanes and the maximum achievable approach speed on the legs of the roundabout. On double-lane circulatory roadways, more than a fourfold relative accident rate was observed, in comparison with single-lane roundabouts located in similar conditions. When the maximum approach speed reached 70 kph or higher, the accident rate was double in comparison with roundabouts where the maximum approach speed was ensured (by means of construction) to be 50 kph or less. Achieved results of the research have been incorporated into the methodology for designing roundabouts, which is certified in the Czech Republic. [ABSTRACT FROM AUTHOR]

The article deals with traffic accidents of pedestrians in the Czech Republic after the methodic of accident monitoring was changed. Till the end of the year 2008 there was an obligation to report every accident where the total damage exceeded amount of 50 000 CZK to the Traffic Police Department. Since the beginning of 2009, this limit was increased to 100 000 CZK. This change had a significant influence on the statistical evaluation of the development of the number of accidents on the roads in the Czech Republic, because at the first sight it might seems like the number of traffic accidents has significantly decreased. However, the actual decrease is related to the accidents reported to the Traffic Police Department. However, this change of the limit has not affected the rating of the evaluation of number of traffic accidents where the participant of accident was injured or died. There is an obligation to report these accidents. The presented article deals with issues of traffic accidents with pedestrians, where we can expect that the pedestrian will be injured after the collision with a vehicle so these accidents are reported to Traffic Police Department. The results of the statistical analysis of traffic accidents before and after the limit change are the main objects of this article. [ABSTRACT FROM AUTHOR]