ESTIMATING THE IMPACTS OF ACCESS MANAGEMENT TECHNIQUES: FINAL RESULTS
This research report summarizes the research activities and findings of the 2.5-year research project to investigate the impacts of access management treatments. The first objective of the project was to estimate the impacts of access management techniques through field data collection at selected sites in Texas and to perform simulation of traffic performance. Findings related to travel time and delay from three case studies are provided in this report. Theoretical corridors were also created and analyzed to provide further insight into corridor performance with changes in median type, driveway density, and traffic volume. The researchers identify key considerations for using microsimulation (VISSIM) for investigating access management treatments. Generally, the research identified a range of differences in travel time (and relatively small changes in speed) when comparing a corridor with a two-way left-turn lane (TWLTL) with the installation of a raised median along the three case study corridors and three theoretical corridors. The reduction in the number of conflict points along the corridors with access management was large (up to 60% for the case studies and up to 75% for the theoretical corridors). The reduction in conflict points illustrates the potential safety impacts of access management. The second objective of the research was to estimate the safety benefits of access management treatments by investigating crash data from select corridors where access management treatments have been installed. A key part of this analysis is the assessment of the crash information used in the analysis. The research identified a relationship between increasing access point density and increasing crash rates. It also identified a reduction in crashes when comparing corridors with a TWLTL with those with a raised median. Crash severity was also reduced with the raised median.
- Project Title: Benefits of Access Management. Report date: May 2004; Resubmitted: October 2004.
College Station, TX United States 77843
Austin, TX United States 78763-5080
Washington, DC United States 20590
- Eisele, W L
- Frawley, W E
- Toycen, C M
- Publication Date: 2004-10
- Features: Appendices; Figures; Photos; References; Tables;
- Pagination: 264 p.
- TRT Terms: Access control (Transportation); Case studies; Crash data; Crash rates; Crash severity; Data collection; Field studies; Impacts; Microsimulation; Traffic conflicts; Traffic delays; Traffic safety; Traffic simulation; Travel time; Two way left turn lanes
- Identifier Terms: VISSIM (Computer model)
- Uncontrolled Terms: Access point density; Raised medians
- Geographic Terms: Texas
- Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;
- Accession Number: 00987638
- Record Type: Publication
- Report/Paper Numbers: FHWA/TX-04/0-4221-2,, Technical Report 0-4221-2
- Contract Numbers: Project No. 0-4221
- Files: TRIS, USDOT, STATEDOT
- Created Date: Mar 7 2005 12:00AM