Development of methodology for traffic calming measure allocation

Speeding has been consistently ranked among the top five primary causes of severe road crashes in the United Arab Emirates (UAE). In fact, speeding has been prevalent even on urban, residential streets where low, area-wide speed limits are the norm. Unfortunately, speeding has resulted in casualties, especially involving pedestrians. This research aims to develop a methodology which estimates spacing between consecutive traffic calming measures (TCMs) which may be effective in keeping vehicle speeds at or below the posted speed limit. This methodology adopted an analytical approach based on: 1) determining the speed reduction effect of different TCMs, and 2) estimating spacing between consecutive TCMs that would effectively control vehicle operating speeds. While literature provides general spacing values which are applicable for all TCMs, distinct TCMs are observed to act differently in terms of speed reduction effectiveness. Therefore, adopting spacing values between TCMs indiscriminately gives rise to stretches of roads between TCMs where motorists reach undesirably high speeds, minimizing the benefits of TCMs. The application of the proposed methodology is demonstrated using scenarios containing speed humps and speed tables. However, the methodology could also be applied to other TCMs such as mini-roundabouts and raised junctions. The output from this study is suitable to UAE’s reality since it relies on local data. The application of the methodology developed in this research is especially recommended within areas where lower speed limits are to be adopted, such as residential streets, downtown areas with significant pedestrian movements, and school zones.