In recent years, in which a considerable increase in the road traffic volumes has been witnessed, traffic calming has become one the key issues in the area of road engineering. This concerns, in particular, trunk roads passing through small villages with a population of up to 500 and the road section length within the village limits of ca. 1400–1700 m. A successful traffic calming scheme must involve primarily effective reduction in inbound traffic speed. A review of the data from various countries revealed that chicanes installed in the transition zones may have a determining effect on the success of the traffic calming project. The effectiveness of such chicanes depends mainly on the type of chicane, its location on the carriageway, its shape and the size of the lateral deflection imposed by the chicane on the inbound lane. The purpose of this study was to identify the speed reduction determinants in traffic calming schemes in village transition zones, based on a central island horizontally deflecting one lane of a two-lane two-way road with 50 km/h speed restriction. As part of the study, vehicle speeds were measured just before and after the chicanes under analysis. Furthermore, the inbound lane traffic volumes were measured in field and a number of factors were identified, including the applied traffic management scheme, road parameters, view of the road ahead and of the village skyline, isolated buildings, road infrastructure and adjacent roadside developments. The obtained data were analysed with a method employing tautologies of the selected 32 factors affecting the drivers’ perception. A single aggregate parameter was proposed for assessing the coincidence of the influence of selected factors on speed reduction. The analysis of the existing schemes and the results of statistical analyses carried out in this study confirmed the authors’ hypothesis that the combined selected factors produce a desirable effect and that they should be additionally enhanced by the application of solar powered devices.

In recent decades traffic calming, especially in villages situated on through roads, has become an urgent issue. Various schemes are applied in the transition zones to reduce the inbound traffic speeds and thus improve the traffic safety. The studies conducted in several countries point to different determinants of the speed reduction obtained in this way. This article deals with the schemes including a central island horizontally deflecting one lane, located in transition zones to villages with 70 km/h speed restriction on two-lane roads (6 m carriageway width). In order to identify the speed reduction determinants, the speeds before and after chicanes were measured and the effect of the three criteria was investigated, characterising: the traffic management scheme, road design parameters, landscape elements present in the surroundings of the transition zone and visibility conditions. Based on the confirmation of logical tautology of many pre-selected factors, one aggregate parameter was proposed for the assessment of the practicable level of speed reduction, combining the effect of the selected factors in the above-mentioned criteria. Statistical analysis of the obtained results confirmed a statistically significant relationship between both the speed reduction value and the speed reduction index, and the aggregate parameter proposed by the authors. Factors related to the surrounding landscape and visibility conditions were found to have the greatest direct effect on speed reduction. The chicanes chosen in the final step of the proposed design process should be enhanced by additional solar-powered elements ensuring their improved visibility. These devices should not, however, require any additional energy supply and should not increase the construction or maintenance costs.

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In the era of increasing traffic volumes and traffic calming problems, the challenges that connect a number of related, although at face value independent, issues involving different social groups seem to be fundamental. The fundamental problem in smaller towns and villages is to ensure the road safety at pedestrian crossings on through roads. The domestic and international guidelines of road design recommend introducing traffic calming devices at places where the traffic enters a built-up area and in central zones, to reduce speeds along the road cutting through a village. One solution is to construct traffic calming devices in the entry zones. As a result, one obtains the so-called speed zoning even before a zone directly related to the scattered or dense housing development. The second issue is to apply traffic calming means in the built-up area. It would seem that the task should pose no difficulty and that it should be the responsibility of the road workers. However, research and analysis into the effectiveness of traffic calming devices show that the best effect is obtained through synergistic efforts of road builders, local authorities, urban planners and many other specialists. The example discussed in the paper, a village of Wrzosowo, clearly supports the thesis. The mere application of traffic calming devices may not necessarily bring the expected results. Combined efforts of road builders and urban planners can, however, be successful in the effective control of speed zoning and reduction in some road sections. The paper presents results of speed reduction measurements of a pedestrian crossing on a regional road in an exemplary village. Measurements of road conditions were conducted three times, before the reconstruction, after it and after the introduction of all the elements of traffic calming, as designed by road builders and urban planners responsible for the development of the vicinity of the road. Analysis of results showed that the chicanes constructed in the entry zones to the village, if used alone, did not provide speed reduction along the throughway cutting through the village. It was only a combination of traffic calming devices and elements of road vicinity development that brought about the expected speed reduction, providing better environmental conditions and improved road safety. Conclusions drawn on the basis of the conducted analysis confirm that the location of chicanes, the use of central reservation strip and traffic barriers must be closely linked to the development of the road vicinity and the location of the road signs that inform motorists about the built-up area.

The on-going growth in the use of motor vehicles leads to a number of traffic safety problems. Therefore, various traffic calming measures are applied to increase traffic safety in built-up areas. Lane narrowing is one of the techniques used to influence the perception of drivers and make them slow down. With this in mind, the authors conducted traffic volume and speed counts before and after installation of the lane narrowing treatment, covering 100 passing vehicles, at an intersection between an urban dual carriageway and an estate street where over a dozen fatal accidents occurred in the recent years. Traffic noise was also measured, both before and after lane narrowing. The traffic count data were analysed to show speed reduction by ca. 15 km/h, yet in all cases still above 50 km/h, which is the speed limit applicable to built-up areas in Poland. The analysis of the “before” and “after” noise maps showed only minor changes to the distribution of noise. The locations of these changes to the acoustic environment depended on the speed and volume of traffic and, much more importantly, on the topography of the surrounding area, the existing roadside layered landscape and the type of planted vegetation. The detailed analyses of the analysed parameters demonstrated that sustainable design of traffic calming measures on urban dual carriageways must consider not only the desired speed reduction but also the surrounding landscape and the local topography.