L&D Manual Turn Lane Storage Validation/Update

Details

• Creators:
  Eustace, Deogratias ; Ponnada, Sowjanya
• Corporate Creators:
  University of Dayton. Department of Civil and Environmental Engineering and Engineering Mechanics
• Corporate Contributors:
  Ohio. Dept. of Transportation ; United States. Federal Highway Administration
• Subject/TRT Terms:
  • Turning lanes
  • Intersections
  • Queuing
  • Traffic congestion
  • Traffic flow
  • Turning lanes
  • Intersections
  • Queuing
  • Traffic congestion
  • Traffic flow
• Publication/ Report Number:
  FHWA/OH-2012/13
• Resource Type:
  Tech Report
• Geographical Coverage:
  Ohio
• Edition:
  Final report.
• Corporate Publisher:
  Ohio. Dept. of Transportation. Office of Research and Development
• Abstract:
  Queuing occurs at intersections mostly due to overflow or inadequacy of turn bays. The ODOT L&D ; Manual Volume 1 has storage requirements for both signalized and unsignalized intersections. Figures ; 401-9E and 401-10E of the L&D Manual provide the required turn lane storage lengths which should be ; compared with the real world conditions to check for adequacy of these lengths as a measure of ensuring ; that accesses to the left turn lanes are not blocked. In addition to the projected turn lane volume, ODOT’s ; methodology incorporates both deceleration (based on the speed of the roadway) and potential blockage ; from the adjacent through lane. Currently, however, there are no records whether these storage lengths ; computed by the methodology put forth in this manual are valid and accurately represent the actual ; conditions at intersections in Ohio. This study used real world traffic and queue storage data at some ; intersections and analyzed these data to validate the model ODOT is currently using. This study used the ; observed field data to evaluate the ODOT’s model of storage length at intersections. In addition, the ; queue storage lengths observed from field data were compared with the prediction results of HCS and ; SYNCHRO computer packages. The model evaluation task evaluated the level of precision of each of the ; three models (ODOT, HCS, and SYNCHRO) with respect to the field data observation. L&D Manual ; lead the way by accurately predicting the observed queues by about 81.6% and closely followed by HCS, ; which also had a 79.2% prediction accuracy. SYNCHRO was by far the lowest with a 46.0% prediction ; accuracy.
  More +
• Format:
  PDF
• Funding:
  134573
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/24934/dot_24934_DS1.pdf
• File Type:
  [PDF - 951.77 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:4f1a219324e2766888c414d5625685e2605c0b757be527a994f7446bb324e21e