Design and Installation Guidelines for Advance Warning Systems for End-of-Green Phase at High Speed Traffic Signals

This report describes the research conducted within a two-year study that developed an effective advance warning for end-of-green phase at high-speed traffic signals in Texas. High-speed signals are defined as having approach speeds of 45 mph or more. The Advance Warning for End-of-Green Signal (AWEGS) was developed in this research by the Texas Transportation Institute for the Texas Department of Transportation (TxDOT). Two AWEGS were designed and the field tests showed a 40-45 percent reduction in red-light running can be expected with well designed, constructed, and maintained systems. This report provides a manual that traffic engineers can use to design and install an AWEGS in the field to improve the safety experience with problematic traffic-actuated signalized intersections. Advance detector design and layout guidelines are provided together with sign design and deployment guidance. A set of uniformly spaced dilemma zone detectors is presumed to be in place on each high-speed approach at the existing traffic actuated signalized intersection to which the AWEGS is envisioned to be added as a safety treatment. A Microsoft¿ Excel-based software, named AWEGS Designer, which can be used to design and layout an AWEGS is available online at http://tti.tamu.edu/documents/0-4260-2-awegs.xls.