Research On On-ramp Control Of Urban Expressway

With the development of economy in China and the increasing size of city,urban car ownership continues to grow.Traffic congestion has become a serious issue.Effective control of expressway on-ramp can improve its traffic capacity and make full use of the existing road resources.It has important theoretical and practical significance to study urban expressway on-ramp control.This paper proposes a multi-on-ramp coordination control algorithm based on genetic algorithm.Specifically,this paper first takes average travel time as evaluation index,and then formulates a multi-on-ramp coordination control model and furthermore designs an effective algorithm.Simulation results verify the effectiveness of the proposed algorithm.Second,taking into account the queue length in the upstream of on-ramp,average number of stops and average stop delay,queue length are introduced as penalty terms to the multi-on-ramp coordination control model for avoiding queue spillover on auxiliary road.Simulation results show the effectiveness of our proposed algorithm.Finally,based on optimization of auxiliary road intersection signal,the expressway,on-ramp and auxiliary road are comprehensively integrated.Considering the average travel time on auxiliary road,a multi-on-ramp control model based on auxiliary road intersection coordination control is proposed and then optimized.The simulation results show that the proposed model can effectively reduce the total travel time of freeway,on-ramp and auxiliary road system,and verify the effectiveness of the proposed algorithm.