Study on Graded Speed Limit in Work Zone Crossovers for Expressway Construction
[Objective]To ensure the vehicles through the work zone crossovers for expressway construction smooth and fast,a graded speed limit plan for the traffic control zone was studied.[Method]Firstly,collect and analyze the traffic flow velocity and time headway in different traffic control zones.Secondly,according to the vehicle trajectory to calculate the value of the last speed limit sign,and a graded speed limit plan for the traffic control zone was formulated based on vehicle deceleration and driver gaze.Finally,the graded speed limit plan was evaluated by safety and efficiency indictors through driving simulator.[Result]The results show that the av-erage speed and the time headway in work zone crossovers are the smallest.When the median width is 70 m,the final speed limit value should be 40 km/h,forming a graded speed limit system in expressway construction with a deceleration amplitude of 20 km/h and a final speed limit sign positioned in 50 m before the up-stream of the transition area.[Conclusion]The driving simulation test shows that compared with the two-level speed limit scheme in JTG H30-2015,the comprehensive efficiency index of the traffic control zone under es-tablished scheme has increased by 9.15%,and the extensive safety index has increased by 27.62%.
expressway constructionwork zone crossovertraffic characteristicstraffic safety and efficiencyspeed limit
万方数据
维普
