Signal Timing Based on Traffic

Current practice on signal timing and coordination is to develop and operate a limited number of timing plans throughout the year and time of day. For example, it is common that coordination plans are developed only for and based on weekday a.m., midday, p.m., off-peak and weekend peak periods. Timing plans are developed in a way that would fit the specific traffic pattern and speed profile during these periods. During the remaining time periods, signals are either operate with a fully-actuated mode or a coordination plan selected based on an engineer's judgment. While the majority of the motorists can benefit from signal coordination during the specific time periods that the coordination plans are developed for, others may experience unsatisfactory travel when no coordination plan is running or the timing plan does not fit the specific traffic pattern. Under inclement weather conditions such as snow, travel speeds would be significantly lower, thus the expected progression would not be achieved. One of the reasons for operating with such limited number of coordination plans is due to resource constraints on signal timing developments. The other reason is perhaps due to limitations of the signal control hardware which only handles a certain number of timing plans. Furthermore, it is unknown whether there will actually be any benefit or whether the benefit will outweigh the cost if additional timing plans are developed and implemented. This proposed research will specifically address these signal timing related issues. Another issue related to signal timing practice is methodologies for determining yellow change and all-red clearance intervals. Current guidelines were developed primarily based on through movements. Left-turn movements have very different characteristics so the current guidelines need to be evaluated for its applicability to left-turn movements.


  • English


  • Status: Active
  • Funding: $61695.00
  • Contract Numbers:


  • Sponsor Organizations:

    Research and Innovative Technology Administration

    University Transportation Centers Program
    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    Nevada Department of Transportation

    1263 South Stewart Street
    Carson City, NV  United States  89712
  • Performing Organizations:

    Transportation Research Center

    University of Nevada, Las Vegas
    4505 Maryland Parkway, MS 4007
    Las Vegas, NV  United States  89154

    University of Nevada, Reno

    College of Engineering
    Reno, NV  United States  89557
  • Principal Investigators:

    Tian, Zong

  • Start Date: 20110601
  • Expected Completion Date: 0
  • Actual Completion Date: 20120630
  • Source Data: RiP Project 32765

Subject/Index Terms

Filing Info

  • Accession Number: 01466748
  • Record Type: Research project
  • Source Agency: Transportation Research Center
  • Contract Numbers: DTRT06-G-0034
  • Created Date: Jan 3 2013 3:22PM