Research On Capacity Of Freeway On-Ramp Junction

Freeway on-ramp junctions are important segments of freeway systems.Because of the confusion taken by the merging behavior of ramp vehicles in merge area,traffic jams and accidents often happen on these segments.Freeway on-ramp junctions become bottlenecks of freeway systems.Therefore,research on capacity of freeway on-ramp junction has great significance for removing bottlenecks,estimating freeway capacity and determining freeway level of service.Firstly,based on a lot of analysis and disposal for investigating data,the characteristics of traffic flow and driver behavior are studied.Secondly,With statistical methods and regression techniques the rules of flow rate and headway distribution for the outside lane are found and the distribution models are set up.Thirdly,the merging behavior of ramp vehicles is analyzed with gap acceptance theory.The maximum traffic flow rate model is established.Fourthly,the linear optimal capacity model of freeway on-ramp junction is set up with linear programming method.Fifthly,capacity of on-ramp junction is analyzed with traffic simulation software named TSIS.Finally,the application analysis of capacity model is carried out with investigating data.The results obtained by the model are compared to the HCM(2000) capacity values and the simulation results.