Optimization Design of Expressway Entrance and Exit Based on Actual Traffic Flow Characteristics

Abstract

The combination area of entrance and exit is the frequent bottleneck of urban expressway system. The running state of traffic flow in combination area is closely related to the key parameters including the acceleration and deceleration lane length, the interweaving area length, the sign identification, etc. And the analysis of traffic flow status can in turn guide the design of road engineering. Therefore, this paper proposes the geometric elements optimization model and design results of the expressway entrance and exit combination area based on the actual traffic flow characteristics and driver’s driving characteristics. To verify the superiority of the optimization model, this paper takes a combination area of Jinzhai Expressway in Hefei City as an example, and after a large number of road traffic surveys, uses VISSIM to simulate and evaluate optimization effect based on proposed model and calculation results. The results show that the optimization model based on traffic flow characteristics is better at improving traffic flow status, especially during the peak period, the average delay of the research section decreased by 18.1%, and the average pass rate of the bottleneck increased by 13.6%.