Research On Traffic Safety Of Connection Line Of Double Horn Interchange Under Free Flow Charging Mode

Under the background of the abolition of provincial border toll station across our country,the ETC system has become the direction for the development and reform of toll collection methods at toll stations on interchanges.This paper is based on the “Three-Dimensional Expansion and Reconstruction of Jihe Expressway” project,which aims to provide solutions and theoretical support for traffic safety-related technical problems on the connecting line sections of the project after the reconstruction of the free-flow toll model of the double-horn interchange.This paper summarizes the relevant research results at home and abroad,puts forward the concept of the free-flow toll model,and determines the location of the ETC gantry on the toll road section of the interchange.Based on the research results at home and abroad,the traffic flow characteristics of the double-horn interchange connection line section are analyzed,and the number of lanes of the weaving segment of the road junction area under different combinations of lane numbers of each merge ramp is analyzed.By establishing a calculation model of the minimum length of the weaving segment of the double-horn interchange connecting line,the minimum weaving segment length is divided into seven components,and then each component is analyzed and solved separately,and finally the limit and general values of the minimum weaving segment length is obtained under different conditions of traffic volume and design speed.Finally,the calculation results were verified with the aid of the VISSIM simulation platform.The paper analyzes and compares the advantages and disadvantages of the current domestic and international mainstream analysis models of interlace capacity and service level operation analysis,selects the calculation model in the HCM2010 as the main research method,and recalibrates the relevant calculation parameters in the model.In the end,the actual capacity and service level of the weaving segment of the connecting line in the eight directions of the four double-horn interchanges of the project were obtained.Finally,in response to the fact that the length of the weaving segment of the existing double-horn interchange is insufficient compared to the calculated minimum weaving segment length,this paper proposes a series of engineering measures,including speed limits and vehicle lane change in advance,which are from the perspective of traffic organization,and adding rightturn ramps,which is from the perspective of engineering design.