Investigation of Dilemma Zone at Signalized Intersections

One of the main problems in densely populated cities is road traffic accidents and traffic jams at the high-speed signalized intersection. In this case, due to the amber light zone, drivers are confused and skeptical for crossing or stopping at stop line of the intersection. Failure to make the right decision in the Dilemma Zone causes fatal accidents at the intersection. In this paper some basic subject about signalized intersection, including the identification of dilemma zone areas, determining boundaries of dilemma zone and affecting factors on this situation, safely protection of dilemma zone and identify the drivers behavior in that area are discussed and some solutions presented. The result of the research show that in order to reduce the rate and severity of crashes and the number of vehicles involved in the dilemma zone areas, increased amber time, all red time and the green light extended system should be used, also if we could use the advanced warning system, it is better to that AWF and CFSSA models should be used before the PTSWF model. Visual stimuli and off-road advertisement are also a very important aberrant behavior of drivers in the dilemma zone areas.