Optimizing Vehicle and Pedestrian Trade-Off Using Signal Timing in Intersections with Center Transit Lanes

Abstract

The construction of exclusive bus lanes is a strategy for giving priority to buses and improving the efficiency of the urban transportation system, and for that purpose, center transit lanes are an important type of transit lane. Along the center transit lanes, the operation of intersections with bus stops becomes more complex because there are four kinds of travelers that need to be organized: buses, private vehicles, crossing pedestrians, and bus passengers. This paper presents a signal timing model for intersections with center transit lanes and bus stops to balance the trade-off between the operations of various users. The optimization model is formulated as a two-objective programming problem. In each subobjective, the weighted average person delay is used. The Pareto frontier of solutions is obtained by iterating all possible combinations of weights for the two objectives. For each combination of weights, the optimization problem becomes a single-objective programming problem. The performance of the proposed model is evaluated using a case study and extensive numerical analyses. A shorter cycle length is recommended to balance the trade-off between vehicles and pedestrians. For the geometric design, a near-side bus stop and larger central refuge island are recommended.