Institute of Transportation, MOTC

    The regulation of hook turn has been implemented for many years in Taiwan. Considering the left-turn risk of motorcyclists in mixed traffic flow, this rule is expected to improve the safety of motorcyclists when they make a turn left. The left-turn waiting area in Taiwan can be classified into three categories, including crossroad left turn waiting area, T-intersection indented left turn waiting area, and T-intersection occupied left turn waiting area. The occupied left turn waiting area is designed to occupy one or part of an outer lane for providing hook turn space for motorcyclists. Previous studies explored the safety and traffic efficiency of this design. This study takes Hsinchu Science Park as an example to explore the actual left-turn behavior of motorcyclists at a T-intersection with occupied left turn waiting area. This study selected three multi-lane T-intersections in the park and collect data by videos. The left-turn behavior of motorcyclists can be classified into four categories, including normal hook turn, abnormal hook turn, opportunistic left-turn, and red light left-turn. Multinomial logistic regression was used to explore the factors associated with different left-turn behaviors of motorcyclists. The results show that increasing full width of the branch, and if other motorcyclists has parked in the left turn waiting area will reduce the probability of opportunistic left-turn and red light left-turn. During peak hours, on weekdays and if other motorcyclists has parked next to divisional islands will increase the probability of opportunistic hook turn. Furthermore, a passenger in the back seat will reduce the probability of red light left-turn. And motorcyclists making a U-turn are more likely to turn left on red.