Effect evaluation of left turn box for bicyclists

Inductive loop technology is essential for detection of road users in order to optimize traffic flows at signalised intersections. Experience shows that bicyclists do not always position themselves on the loops, resulting in reduced passability. This paper evaluates the effect of a marked box for left turning cyclists placed over the induction loop in signalised intersections via a with/without study and a before/after study. The with/without study in four intersections shows 0-44% placement on the loop without the left turn box compared to 61-89% with the left turn box, respectively. The before/after study in one intersection shows a statistically significant increase in the correct position from 0-11% before and 18-48% after, respectively. The left turn boxes have a significant positive effect on the position of the bicyclists, but also the clarity of the intersection design is important for the correct use of the induction loops.