False capacity for lane drops : final report.

Details

• Creators:
  Lee, Jae-Joon ; Hummer, Joseph E. ; Rouphail, Nagui M.
• Corporate Creators:
  North Carolina State University. Department of Civil, Construction, and Environmental Engineering ; University of North Carolina (System). Institute for Transportation Research and Education
• Corporate Contributors:
  North Carolina. Dept. of Transportation. Research and Analysis Group ; United States. Federal Highway Administration
• Subject/TRT Terms:
  • Crash data
  • Data collection
  • Highway capacity
  • Lane drops
  • Multiple regression analysis
  • Signalized intersections
  • Traffic data
  • Traffic safety Lane distribution
• Publication/ Report Number:
  FHWA/NC/2005-01;NCDOT Research Project 2003-07
• Resource Type:
  Research Paper
• Geographical Coverage:
  United States;North Carolina
• Edition:
  Final Report, July 2002 - June 2004
• Corporate Publisher:
  North Carolina. Department of Transportation
• Abstract:
  Lane drops downstream of signalized intersections are found on many urban and suburban streets and highways. Since ; drivers tend to avoid using the short lane due to the potential for stressful merges downstream of the signal, the short lane is ; typically under-utilized. Previous research indicates that the default lane utilization factors in the Highway Capacity Manual ; (HCM) appear to overestimate traffic in the short lane. The purpose of this project was to develop models to predict lane ; utilization factors for six defined intersection types and to assess how a lane drop affects safety near intersections. ; Traffic, signal, and collision data were collected at 94 sites in North Carolina. Based on 15 candidate factors, multiple ; regression models were developed for the purpose of predicting the lane utilization factor. This study found that the downstream ; lane length and traffic intensity positively correlate with the lane utilization factor, and that some geometric variables at the ; approach may also influence lane utilization. Collision data analysis results show that collision rates downstream of an ; intersection decline as the distance to a lane drop increase. The results also show that the lane drop type does not affect collision ; rates upstream and downstream of intersections. ; Many of the results derived from this study are consistent with previous research. The models developed should provide ; designers and traffic engineers with concrete methods to improve lane utilization when lane drops are contemplated. ; A re-assessment of the effect of lane utilization on capacity is recommended, since models in the HCM consistently ; overestimate delay for all types of lane drop intersections with low lane utilization.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/16164/dot_16164_DS1.pdf
• File Type:
  [PDF - 973.59 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:549fd7271b3b64c2de35efbd1aa10e3aa7b499cf2a60657aecb97e419d5c807f955be7037dad3b70e04ad92a6277d31a0dceffa71b67c8527ef0447283ecbce9