Influence of Countdown of Green Signal on Traffic Safety at Crossing

Based on the review of related research at home and abroad,the influence of the countdown of green signal on driver's psychology and driving behaviors is investigated through questionnaire investigation and field observation,and the influencing mechanism is also analyzed.It shows that green signal countdown is either good to traffic safety,nor to the traffic efficiency.Therefore,the countdown of green signal should be used with care.It is suggested to modify the definition of yellow signal in road traffic safety law and add over-speeding snapping function during yellow signal to the red-light running snap system in order to reduce the occurrence of over-speeding phenomenon during signal transition and guarantee the traffic safety.