1 / 8

Road Traffic Flow & Speed Data Acquisition & Cleaning

Road Traffic Flow & Speed Data Acquisition & Cleaning. Andrew Jellyman & Peter Fallon Birmingham City Council. For each road BUMP requires: The total number of vehicle movements as either: An 18 hour flow, or 18 hourly flows % heavy goods vehicles Vehicle speeds or speed limits Road type

quennell-poirier
Télécharger la présentation

Road Traffic Flow & Speed Data Acquisition & Cleaning

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Road Traffic Flow & Speed Data Acquisition & Cleaning Andrew Jellyman & Peter Fallon Birmingham City Council

  2. For each road BUMP requires: • The total number of vehicle movements as either: • An 18 hour flow, or • 18 hourly flows • % heavy goods vehicles • Vehicle speeds or speed limits • Road type • Gradient • Road surface type (Concrete/Asphalt) • Texture depth (asphalt only)

  3. A decision was made at an early stage of the project to use the Policy Responsive Integrated Strategy Model (PRISM) transportation model operated on behalf of the West Midlands local authorities This model is intended for transportation planning and was adapted to provide the necessary road traffic flows and speeds for BUMP However, it does not provide data on road type, gradient or surface

  4. The PRISM model could not be used directly for BUMP due to spatial inaccuracies Here the road in PRISM actually touches the buildings! The correct road position is shown in red

  5. There are also many more roads in Birmingham than are included in PRISM Only the roads shown in blue are included in the PRISM model. Default data had to be assigned to the remaining roads

  6. Because of the limitations of the geographical accuracy of the PRISM model and the generalised nature of the data set, it was decided to use the Ordnance Survey Integrated Transport Network (ITN) theme in MasterMap for BUMP Flow and speed data could have been manually assigned from the PRISM data set to ITN but this would have been a huge task The noise mapping software includes routines to assign data based on location. This facility was used to ‘spatially’ assign speed and flow data from PRISM to ITN However, this only worked for about 40% of the 5700 Km of roads in the BUMP area

  7. Care had to be taken that assignments were correct, for example where two roads were close together The remaining roads had to be assigned manually, and two students were employed for 3 months to do this Some road junctions were too complex for the students to understand and two officers from the BUMP team had to spend considerable time completing and validating the process Many ‘minor’ roads are not included in the PRISM data and default data had to be assigned to these

  8. As there are no concrete roads within the BUMP area, road type is not an issue for the Project. However, texture depth information proved impossible to obtain so a default value was used Road gradients are determined internally by the noise mapping software based on terrain height

More Related