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In recent years, speed reduction measures have been increasingly used, especially in heavily urbanised areas. If local conditions allow, traffic-calming schemes are implemented, which include a variety of traffic-calming measures (TCM). Some of the most common traffic-calming measures are concrete block paved vertical traffic-calming devices (VTCDs), including speed tables, speed humps, speed bumps and raised pedestrian crossings. Different design and construction recommendations apply to the respective VTCD types. The aim of this article is to examine the effectiveness of VTCDs in speed reduction and the impact of horizontal forces on pavement conditions, both within and beyond VTCDs, after over a dozen years of exposure to traffic. For this purpose, speed surveys were carried out on selected two-way streets running through home zones in Poland. The pavements on selected VTCDs were identified and visually assessed for damage, and subsidence areas were estimated using the terrestrial laser scanning (TSL) technique. The analysis resulted in the development of the Deviation Model 3D (DM3D), showing local deviations from the theoretical surface, obtained by superimposing the two models, the Real Surface Digital Terrain Model (RS DTM) and the Theoretical Surface Digital Terrain Model (TS DTM). A comparative analysis of the pavement surface condition and the magnitudes of horizontal forces allowed us to identify the locations of critical spots in VTCDs. The results were used as the basis for developing recommended pavement structures and deriving engineering recommendations for concrete block paving in VTCDs. [ABSTRACT FROM AUTHOR]

Contemporary street space upgrade or regeneration projects tend to include setting up home zones that are located in large city suburbs, smaller towns or spas. These home zones feature one-way streets, merging of a pavement and carriageway into one level surface and various traffic calming measures (TCM), including speed tables and traffic circles (TC). Concrete paving blocks are the preferred surfacing material. As part of this study, traffic surveys were carried out in a small seaside spa in Poland to determine the accelerations and decelerations of vehicles passing through four traffic circles that have different central island heights and different streetscape characteristics. A visual assessment of the pavement condition was also carried out. The pavement deformation changes were analysed using 3D models derived on the basis of the terrestrial laser scanning data obtained with the Trimble SX10 scanning total station. The existing pavement structure was analysed as part of this study. Next, the areas that require strengthening were identified based on subsidence and horizontal forces analyses, with the latter calculated from the observed decelerations and accelerations of the passing vehicles. Finally, design guidelines are given for concrete block surfacing in high traffic impact locations. [ABSTRACT FROM AUTHOR]