TWO-STEP OPTIMIZATION MODEL FOR DYNAMIC LANE ASSIGNMENT AT ISOLATED SIGNALIZED INTERSECTIONS

摘要

At isolated signalized intersections, the congestion problem is partly caused by the unbalance ofsupply and demand which may be due to the variability of turning movement volumes. Althoughthe signal timing can be adjusted to handle varying demand, its effect alone is limited, especiallywhen the traffic demand fluctuates significantly. This paper presented a two-step optimizationmodel for dynamic lane assignment to overcome this shortcoming of static lane markings andfully utilize the existing traffic facilities. The first step was to obtain the best lane assignmentscheme by an arm-group based Integer-Non-Linear-Program model. The second step was toidentify a suitable implementation scheme by determining a binary-type threshold. The results ofVISSIM simulation showed that the proposed model could smartly choose the occasion tochange the lane assignment by ignoring the small volume fluctuation and improve the trafficoperation effectively when the traffic demand varies significantly.