Study On Selection Of Super-Multi-lane Expressway Traffic Organization Mode Based On Traffic Efficiency In Merging Area

In some economically developed areas such as the Pearl River Delta and the Yangtze River Delta,the reconstruction and expansion plan of the super-multi-lane expressway with ten lanes or more in two directions are rising.In order to optimize the traffic efficiency,super-multi-lane expressways often adopt some traffic organization methods different from that of low-lane expressways.In this context,how to choose the methods of traffic organization has become an urgent problem to be solved in the reconstruction and expansion of super-multi-lane expressways.This paper takes the merge area of super-multilane expressway as the bottleneck section that restricts the choices of traffic organization method,comparatively studied the traffic efficiency of the super-multi-lane expressway under the traffic organization methods of integral,passenger-freight separated and mainauxiliary separated,which has a good reference significance for the selection of traffic organization of super-multi-lane expressway.This paper firstly studied the domestic and foreign applications of the three types of traffic organization methods and the traffic characteristics of the confluence area,and summarizes and analyzes the factors affecting the capacity and the classification of traffic conflict and indicators.Then,a model for the applicability of the confluence area capacity under the three traffic organization modes based on the micro-simulation method was established.The parameters of the driving behavior model were corrected using the measured data of the GuangShen expressway.The capacity model of the confluence area of common lane combinations under eight,ten and twelve lanes has been calibrated with parameters.The maximum capacity value of the main line under dynamic merging flow is obtained.The paper then studied the traffic conflicts in the merging area under the three types of traffic organization methods,using micro-simulation method combined with SSAM software,using TTC as the traffic conflict indicator,and studied the characteristics of traffic conflicts of the representative two-way ten-lane expressways’merging area.The severity threshold of traffic conflicts and the lane distribution characteristics of rear-end collisions and lateral conflicts under the three types of traffic organization modes are analyzed.Finally,this paper combines the above research,adopts the AHP-fuzzy comprehensive evaluation method,takes capacity,traffic conflict,and engineering economy as the three evaluation indicators,and conducts the three types of traffic organization methods in the merging area of the Changan-Xinqiao section in GuangShen expressway.The efficiency evaluation concluded that the combination of passenger-freight separated"3+2" is most suitable for this segment.The method is also applied to the entire Shenzhen section of GuangShen expressway,and suggestions for traffic organization method in different sections are given.The capacity model of the merging area of the three types of traffic organization modes under the dynamic confluence flow studied in this paper has strong applicability and can accurately solve the main line capacity under different confluence flows.Research on traffic conflicts shows that the separation of passenger and cargo can effectively reduce the conflict between vehicles in the expressway confluence area.The comprehensive evaluation model of traffic efficiency established by the study of Traffic Capacity and Traffic Conflict can effectively obtain the best traffic organization plan for super-multi-lane expressways,which has good engineering practical significance.